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Extension attribute redistribution
Setting the maximum lifetime for routes and labels in the RIB
Setting the maximum lifetime for routes in the FIB
Configuring inter-protocol FRR
Configuring IPv4 RIB inter-protocol FRR
Configuring IPv6 RIB inter-protocol FRR
Enabling the IPv4 enhanced ECMP mode
Displaying and maintaining a routing table
Configuring BFD for static routes
Configuring static route FRR by specifying a backup next hop
Configuring static route FRR to automatically select a backup next hop
Enabling BFD echo packet mode for static route FRR
Displaying and maintaining static routes
Static route configuration examples
Basic static route configuration example
BFD for static routes configuration example (direct next hop)
BFD for static routes configuration example (indirect next hop)
Static route FRR configuration example
Controlling RIP reception and advertisement on interfaces
Configuring an additional routing metric
Configuring RIPv2 route summarization··
Disabling host route reception
Configuring received/redistributed route filtering
Configuring RIP route redistribution
Tuning and optimizing RIP networks
Enabling split horizon and poison reverse
Setting the maximum number of RIP ECMP routes
Enabling zero field check on incoming RIPv1 messages
Enabling source IP address check on incoming RIP updates
Configuring RIPv2 message authentication
Setting the RIP triggered update interval
Configuring RIP network management
Configuring the RIP packet sending rate·
Setting the maximum length of RIP packets
Setting the DSCP value for outgoing RIP packets
Configuring single-hop echo detection (for a directly connected RIP neighbor)
Configuring single-hop echo detection (for a specific destination)
Configuring bidirectional control detection
Configuration restrictions and guidelines
Displaying and maintaining RIP
Configuring RIP route redistribution
Configuring an additional metric for a RIP interface
Configuring RIP to advertise a summary route
Configuring BFD for RIP (single-hop echo detection for a directly connected neighbor)
Configuring BFD for RIP (single hop echo detection for a specific destination)
Configuring BFD for RIP (bidirectional detection in BFD control packet mode)
Configuring OSPF network types
Configuring the broadcast network type for an interface
Configuring the NBMA network type for an interface
Configuring the P2MP network type for an interface
Configuring the P2P network type for an interface
Configuring OSPF route control
Configuring OSPF route summarization··
Configuring received OSPF route filtering·
Configuring Type-3 LSA filtering
Setting an OSPF cost for an interface
Setting the maximum number of ECMP routes
Configuring discard routes for summary networks
Configuring OSPF route redistribution··
Excluding interfaces in an OSPF area from the base topology
Tuning and optimizing OSPF networks
Setting LSA transmission delay
Setting SPF calculation interval
Setting the LSA arrival interval
Setting the LSA generation interval
Disabling interfaces from receiving and sending OSPF packets
Configuring OSPF authentication
Adding the interface MTU into DD packets·
Setting the DSCP value for outgoing OSPF packets
Setting the maximum number of external LSAs in LSDB
Setting OSPF exit overflow interval
Enabling compatibility with RFC 1583
Logging neighbor state changes
Configuring OSPF network management
Setting the maximum length of OSPF packets that can be sent by an interface
Configuring prefix suppression
Configuring prefix prioritization
Setting the number of OSPF logs
Filtering outbound LSAs on an interface·
Filtering LSAs for the specified neighbor
Configuring bidirectional control detection
Configuring single-hop echo detection
Advertising OSPF link state information to BGP
Displaying and maintaining OSPF
Basic OSPF configuration example
OSPF route redistribution configuration example
OSPF route summarization configuration example
OSPF stub area configuration example
OSPF NSSA area configuration example
OSPF DR election configuration example
OSPF virtual link configuration example
OSPF NSR configuration example
BFD for OSPF configuration example
OSPF FRR configuration example
Troubleshooting OSPF configuration
No OSPF neighbor relationship established
Setting the IS level and circuit level
Configuring P2P network type for an interface
Configuring IS-IS route control
Specifying a preference for IS-IS··
Configuring the maximum number of ECMP routes
Configuring IS-IS route summarization··
Configuring IS-IS route redistribution··
Configuring IS-IS route filtering
Configuring IS-IS route leaking
Tuning and optimizing IS-IS networks
Specifying the interval for sending IS-IS hello packets
Specifying the IS-IS hello multiplier
Specifying the interval for sending IS-IS CSNP packets
Configuring a DIS priority for an interface
Disabling an interface from sending/receiving IS-IS packets
Enabling an interface to send small hello packets
Controlling SPF calculation interval
Configuring convergence priorities for specific routes
Configuring the tag value for an interface
Configuring system ID to host name mappings
Enabling the logging of neighbor state changes
Configuring IS-IS network management
Enhancing IS-IS network security
Configuring neighbor relationship authentication
Configuring area authentication
Configuring routing domain authentication
Displaying and maintaining IS-IS
Basic IS-IS configuration example
DIS election configuration example
IS-IS route redistribution configuration example
IS-IS authentication configuration example
IS-IS GR configuration example
IS-IS NSR configuration example
BFD for IS-IS configuration example
IS-IS FRR configuration example
BGP route advertisement rules·
Settlements for problems in large-scale BGP networks
Specifying the source address of TCP connections
Controlling route distribution and reception
Configuring BGP route summarization
Advertising optimal routes in the IP routing table
Advertising a default route to a peer or peer group
Limiting routes received from a peer or peer group
Configuring BGP route filtering policies
Configuring BGP route update delay
Configuring BGP route dampening
Controlling BGP path selection
Setting a preferred value for routes received
Configuring preferences for BGP routes
Configuring the default local preference
Configuring the NEXT_HOP attribute
Configuring the AS_PATH attribute
Ignoring IGP metrics during optimal route selection
Tuning and optimizing BGP networks
Configuring the keepalive interval and hold time
Configuring the interval for sending updates for the same route
Enabling BGP to establish an EBGP session over multiple hops
Enabling immediate re-establishment of direct EBGP connections upon link failure
Enabling 4-byte AS number suppression
Enabling MD5 authentication for BGP peers
Enabling keychain authentication for BGP peers
Configuring BGP load balancing
Disabling BGP to establish a session to a peer or peer group
Protecting an EBGP peer when memory usage reaches level 2 threshold
Configuring an update delay for local MPLS labels
Flushing the suboptimal BGP route to the RIB
Setting a DSCP value for outgoing BGP packets
Enabling per-prefix label allocation
Disabling optimal route selection for labeled routes without tunnel information
Configuring a large-scale BGP network
Configuring BGP route reflection
Configuring a BGP confederation
Enabling SNMP notifications for BGP
Enabling logging for session state changes
Enabling logging for BGP route flapping
Configuring optional 6PE capabilities
Configuring BGP LS route reflection
Specifying an AS number and a router ID for BGP LS messages
Displaying and maintaining BGP
IPv4 BGP configuration examples
Basic BGP configuration example
BGP and IGP route redistribution configuration example
BGP route summarization configuration example
BGP load balancing configuration example
BGP community configuration example
BGP route reflector configuration example
BGP confederation configuration example
BGP path selection configuration example
BFD for BGP configuration example
Multicast BGP configuration example
Dynamic BGP peer configuration example
IPv6 BGP configuration examples
IPv6 BGP basic configuration example
IPv6 BGP route reflector configuration example
BFD for IPv6 BGP configuration example
IPv6 BGP FRR configuration example
Restrictions and guidelines: PBR configuration
Setting match criteria for a node·
Configuring actions for a node
Specifying a policy for local PBR
Specifying a policy for interface PBR
Specifying a policy for outbound PBR on a VXLAN tunnel interface
Displaying and maintaining PBR
Packet type-based local PBR configuration example
Packet type-based interface PBR configuration example
Configuring IPv6 static routing
Configuring an IPv6 static route
Configuring BFD for IPv6 static routes
Displaying and maintaining IPv6 static routes
IPv6 static routing configuration examples
Basic IPv6 static route configuration example
BFD for IPv6 static routes configuration example (direct next hop)
BFD for IPv6 static routes configuration example (indirect next hop)
Configuring an IPv6 default route
Configuring RIPng route control
Configuring an additional routing metric
Configuring RIPng route summarization··
Configuring received/redistributed route filtering
Setting a preference for RIPng
Configuring RIPng route redistribution··
Tuning and optimizing the RIPng network
Configuring split horizon and poison reverse
Configuring zero field check on RIPng packets
Setting the maximum number of ECMP routes
Configuring the RIPng packet sending rate·
Setting the interval for sending triggered updates
Configuration restrictions and guidelines
Displaying and maintaining RIPng
Basic RIPng configuration example
RIPng route redistribution configuration example
RIPng GR configuration example
RIPng NSR configuration example
OSPFv3 configuration task list
Configuring OSPFv3 area parameters
Configuring an OSPFv3 virtual link
Configuring OSPFv3 network types
Configuring the OSPFv3 network type for an interface
Configuring an NBMA or P2MP neighbor
Configuring OSPFv3 route control
Configuring OSPFv3 route summarization··
Configuring OSPFv3 received route filtering
Configuring Inter-Area-Prefix LSA filtering
Setting an OSPFv3 cost for an interface
Setting the maximum number of OSPFv3 ECMP routes
Setting a preference for OSPFv3
Configuring OSPFv3 route redistribution··
Tuning and optimizing OSPFv3 networks
Setting LSA transmission delay
Setting SPF calculation interval
Setting the LSA generation interval
Setting a DR priority for an interface
Ignoring MTU check for DD packets
Disabling interfaces from receiving and sending OSPFv3 packets
Enabling logging for neighbor state changes
Configuring OSPFv3 network management
Configuring prefix suppression
Setting the maximum number of OSPFv3 logs
Configuring OSPFv3 authentication
Displaying and maintaining OSPFv3
OSPFv3 stub area configuration example
OSPFv3 NSSA area configuration example
OSPFv3 DR election configuration example
OSPFv3 route redistribution configuration example
OSPFv3 route summarization configuration example
OSPFv3 GR configuration example
OSPFv3 NSR configuration example
BFD for OSPFv3 configuration example
OSPFv3 FRR configuration example
Configuring IPv6 IS-IS route control
Configuring IPv6 IS-IS link cost
Tuning and optimizing IPv6 IS-IS networks·
Assigning a convergence priority to IPv6 IS-IS routes
Configuring a tag value on an interface
Controlling SPF calculation interval
Configuring BFD for IPv6 IS-IS
Displaying and maintaining IPv6 IS-IS
IPv6 IS-IS configuration examples
IPv6 IS-IS basic configuration example
BFD for IPv6 IS-IS configuration example
IPv6 IS-IS FRR configuration example
Restrictions and guidelines: IPv6 PBR configuration
IPv6 PBR configuration task list
Setting match criteria for an IPv6 node
Configuring actions for an IPv6 node
Configuring IPv6 interface PBR
Displaying and maintaining IPv6 PBR··
IPv6 PBR configuration examples
Packet type-based IPv6 local PBR configuration example
Packet type-based IPv6 interface PBR configuration example
Configuring an extended community list
Configuring the continue clause
Displaying and maintaining the routing policy
Routing policy configuration examples
Routing policy configuration example for IPv4 route redistribution
Routing policy configuration example for IPv6 route redistribution
Configuring basic IP routing
IP routing directs IP packet forwarding on routers based on a routing table. This chapter focuses on unicast routing protocols. For more information about multicast routing protocols, see IP Multicast Configuration Guide.
Routing table
A RIB contains the global routing information and related information, including route recursion, route redistribution, and route extension information. The router selects optimal routes from the routing table and puts them into the FIB table. It uses the FIB table to forward packets. For more information about the FIB table, see Layer 3—IP Services Configuration Guide.
Table 1 categorizes routes by different criteria.
Criterion |
Categories |
Destination |
· Network route—The destination is a network. The subnet mask is less than 32 bits. · Host route—The destination is a host. The subnet mask is 32 bits. |
Whether the destination is directly connected |
· Direct route—The destination is directly connected. · Indirect route—The destination is indirectly connected. |
Origin |
· Direct route—A direct route is discovered by the data link protocol on an interface, and is also called an interface route. · Static route—A static route is manually configured by an administrator. · Dynamic route—A dynamic route is dynamically discovered by a routing protocol. |
To view brief information about a routing table, use the display ip routing-table command.
<Sysname> display ip routing-table
Destinations : 9 Routes : 9
Destination/Mask Proto Pre Cost NextHop Interface
0.0.0.0/32 Direct 0 0 127.0.0.1 InLoop0
3.3.3.3/32 Direct 0 0 127.0.0.1 InLoop0
127.0.0.0/8 Direct 0 0 127.0.0.1 InLoop0
127.0.0.0/32 Direct 0 0 127.0.0.1 InLoop0
127.0.0.1/32 Direct 0 0 127.0.0.1 InLoop0
127.255.255.255/32 Direct 0 0 127.0.0.1 InLoop0
...
A route entry includes the following key items:
· Destination—IP address of the destination host or network.
· Mask—Mask length of the IP address.
· Proto—Protocol that installed the route.
· Pre—Preference of the route. Among routes to the same destination, the route with the highest preference is optimal.
· Cost—If multiple routes to a destination have the same preference, the one with the smallest cost is the optimal route.
· NextHop—Next hop.
· Interface—Output interface.
Dynamic routing protocols
Static routes work well in small, stable networks. They are easy to configure and require fewer system resources. However, in networks where topology changes occur frequently, a typical practice is to configure a dynamic routing protocol. Compared with static routing, a dynamic routing protocol is complicated to configure, requires more router resources, and consumes more network resources.
Dynamic routing protocols dynamically collect and report reachability information to adapt to topology changes. They are suitable for large networks.
Dynamic routing protocols can be classified by different criteria, as shown in Table 2.
Table 2 Categories of dynamic routing protocols
Criterion |
Categories |
Operation scope |
· IGPs—Work within an AS. Examples include RIP, OSPF, and IS-IS. · EGPs—Work between ASs. The most popular EGP is BGP. |
Routing algorithm |
· Distance-vector protocols—Examples include RIP and BGP. BGP is also considered a path-vector protocol. · Link-state protocols—Examples include OSPF and IS-IS. |
Destination address type |
· Unicast routing protocols—Examples include RIP, OSPF, BGP, and IS-IS. · Multicast routing protocols—Examples include PIM-SM and PIM-DM. |
IP version |
· IPv4 routing protocols—Examples include RIP, OSPF, BGP, and IS-IS. · IPv6 routing protocols—Examples include RIPng, OSPFv3, IPv6 BGP, and IPv6 IS-IS. |
An AS refers to a group of routers that use the same routing policy and work under the same administration.
Route preference
Routing protocols, including static and direct routing, each by default have a preference. If they find multiple routes to the same destination, the router selects the route with the highest preference as the optimal route.
The preference of a direct route is always 0 and cannot be changed. You can configure a preference for each static route and each dynamic routing protocol. The following table lists the route types and default preferences. The smaller the value, the higher the preference.
Table 3 Route types and default route preferences
Route type |
Preference |
Direct route |
0 |
Multicast static route |
1 |
OSPF |
10 |
IS-IS |
15 |
Unicast static route |
60 |
RIP |
100 |
OSPF ASE |
150 |
OSPF NSSA |
150 |
IBGP |
255 |
EBGP |
255 |
Unknown (route from an untrusted source) |
256 |
Load sharing
A routing protocol might find multiple optimal equal-cost routes to the same destination. You can use these routes to implement equal-cost multi-path (ECMP) load sharing.
Static routing, IPv6 static routing, RIP, RIPng, OSPF, OSPFv3, BGP, IPv6 BGP, IS-IS, and IPv6 IS-IS support ECMP load sharing.
Route backup
Route backup can improve network availability. Among multiple routes to the same destination, the route with the highest priority is the primary route and others are secondary routes.
The router forwards matching packets through the primary route. When the primary route fails, the route with the highest preference among the secondary routes is selected to forward packets. When the primary route recovers, the router uses it to forward packets.
Route recursion
To use a BGP, static, or RIP route that has an indirectly connected next hop, a router must perform route recursion to find the output interface to reach the next hop.
Link-state routing protocols, such as OSPF and IS-IS, do not need route recursion, because they obtain directly connected next hops through route calculation.
The RIB records and saves route recursion information, including brief information about related routes, recursive paths, and recursion depth.
Route redistribution
Route redistribution enables routing protocols to learn routing information from each other. A dynamic routing protocol can redistribute routes from other routing protocols, including direct and static routing. For more information, see the respective chapters on those routing protocols in this configuration guide.
The RIB records redistribution relationships of routing protocols.
Extension attribute redistribution
Extension attribute redistribution enables routing protocols to learn route extension attributes from each other, including BGP extended community attributes, OSPF area IDs, route types, and router IDs.
The RIB records extended attributes of each routing protocol and redistribution relationships of different routing protocol extended attributes.
Setting the maximum lifetime for routes and labels in the RIB
Perform this task to prevent routes of a certain protocol from being aged out due to slow protocol convergence resulting from a large number of route entries or long GR period.
The configuration takes effect at the next protocol or RIB process switchover.
To set the maximum lifetime for routes and labels in the RIB (IPv4):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIB view. |
rib |
N/A |
3. Create the RIB IPv4 address family and enter its view. |
address-family ipv4 |
By default, no RIB IPv4 address family exists. |
4. Set the maximum lifetime for IPv4 routes and labels in the RIB. |
protocol protocol [ instance instance-name ] lifetime seconds |
By default, the maximum lifetime for routes and labels in the RIB is 480 seconds. |
To set the maximum route lifetime for routes and labels in the RIB (IPv6):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIB view. |
rib |
N/A |
3. Create the RIB IPv6 address family and enter its view. |
address-family ipv6 |
By default, no RIB IPv6 address family exists. |
4. Set the maximum lifetime for IPv6 routes and labels in the RIB. |
protocol protocol [ instance instance-name ] lifetime seconds |
By default, the maximum lifetime for routes and labels in the RIB is 480 seconds. |
Setting the maximum lifetime for routes in the FIB
When GR or NSR is disabled, FIB entries must be retained for some time after a protocol process switchover or RIB process switchover. When GR or NSR is enabled, FIB entries must be removed immediately after a protocol or RIB process switchover to avoid routing issues. Perform this task to meet such requirements.
To set the maximum lifetime for routes in the FIB (IPv4):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIB view. |
rib |
N/A |
3. Create the RIB IPv4 address family and enter its view. |
address-family ipv4 |
By default, no RIB IPv4 address family exists. |
4. Set the maximum lifetime for IPv4 routes in the FIB. |
fib lifetime seconds |
By default, the maximum lifetime for routes in the FIB is 600 seconds. |
To set the maximum lifetime for routes in the FIB (IPv6):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIB view. |
rib |
N/A |
3. Create the RIB IPv6 address family and enter its view. |
address-family ipv6 |
By default, no RIB IPv6 address family exists. |
4. Set the maximum lifetime for IPv6 routes in the FIB. |
fib lifetime seconds |
By default, the maximum lifetime for routes in the FIB is 600 seconds. |
Configuring RIB NSR
|
IMPORTANT: Use this feature with protocol GR or NSR to avoid route timeouts and traffic interruption. |
When an active/standby switchover occurs, nonstop routing (NSR) backs up routing information from the active process to the standby process to avoid routing flapping and ensure forwarding continuity.
RIB NSR provides faster route convergence than protocol NSR during an active/standby switchover.
Configuring IPv4 RIB NSR
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIB view. |
rib |
N/A |
3. Create the RIB IPv4 address family and enter its view. |
address-family ipv4 |
By default, no RIB IPv4 address family exists. |
4. Enable IPv4 RIB NSR. |
non-stop-routing |
By default, RIB NSR is disabled. |
Configuring IPv6 RIB NSR
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIB view. |
rib |
N/A |
3. Create the RIB IPv6 address family and enter its view. |
address-family ipv6 |
By default, no RIB IPv6 address family exists. |
4. Enable IPv6 RIB NSR. |
non-stop-routing |
By default, RIB NSR is disabled. |
Configuring inter-protocol FRR
|
CAUTION: This feature uses the next hop of a route from a different protocol as the backup next hop for the faulty route, which might cause loops. |
Inter-protocol fast reroute (FRR) enables fast rerouting between routes of different protocols. A backup next hop is automatically selected to reduce the service interruption time caused by unreachable next hops. When the next hop of the primary link fails, the traffic is redirected to the backup next hop.
Among the routes to the same destination in the RIB, a router adds the route with the highest preference to the FIB table. For example, if a static route and an OSPF route in the RIB have the same destination, the router adds the OSPF route to the FIB table by default. The next hop of the static route is selected as the backup next hop for the OSPF route. When the next hop of the OSPF route is unreachable, the backup next hop is used.
Configuring IPv4 RIB inter-protocol FRR
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIB view. |
rib |
N/A |
3. Create the RIB IPv4 address family and enter its view. |
address-family ipv4 |
By default, no RIB IPv4 address family exists. |
4. Enable IPv4 RIB inter-protocol FRR. |
inter-protocol fast-reroute [ vpn-instance vpn-instance-name ] |
By default, inter-protocol FRR is disabled. If you do not specify a VPN instance, inter-protocol FRR is enabled for the public network. |
Configuring IPv6 RIB inter-protocol FRR
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIB view. |
rib |
N/A |
3. Create the RIB IPv6 address family and enter its view. |
address-family ipv6 |
By default, no RIB IPv6 address family exists. |
4. Enable IPv6 RIB inter-protocol FRR. |
inter-protocol fast-reroute [ vpn-instance vpn-instance-name ] |
By default, inter-protocol FRR is disabled. If you do not specify a VPN instance, inter-protocol FRR is enabled for the public network. |
Enabling the IPv4 enhanced ECMP mode
When one or multiple ECMP routes fail, the default ECMP mode enables the device to reallocate all traffic to the remaining routes.
The IPv4 enhanced ECMP mode enables the device to reallocate only the traffic of the failed routes to the remaining routes, which ensures forwarding continuity.
This configuration takes effect at reboot. Make sure the reboot does not impact your network.
To enable the IPv4 enhanced ECMP mode:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enable the IPv4 enhanced ECMP mode. |
ecmp mode enhanced |
By default, the IPv4 enhanced ECMP mode is disabled. |
Displaying and maintaining a routing table
Execute display commands in any view and reset commands in user view.
Task |
Command |
Display the IPv4 ECMP mode. |
display ecmp mode |
Display routing table information. |
display ip routing-table [ vpn-instance vpn-instance-name ] [ verbose ] |
Display information about routes permitted by an IPv4 basic ACL. |
display ip routing-table [ vpn-instance vpn-instance-name ] acl ipv4-acl-number [ verbose ] |
Display information about routes to a specific destination address. |
display ip routing-table [ vpn-instance vpn-instance-name ] ip-address [ mask-length | mask ] [ longer-match ] [ verbose ] |
Display information about routes to a range of destination addresses. |
display ip routing-table [ vpn-instance vpn-instance-name ] ip-address1 to ip-address2 [ verbose ] |
Display information about routes permitted by an IP prefix list. |
display ip routing-table [ vpn-instance vpn-instance-name ] prefix-list prefix-list-name [ verbose ] |
Display information about routes installed by a protocol. |
display ip routing-table [ vpn-instance vpn-instance-name ] protocol protocol [ inactive | verbose ] |
Display IPv4 route statistics. |
display ip routing-table [ vpn-instance vpn-instance-name ] statistics |
Display brief IPv4 routing table information. |
display ip routing-table [ vpn-instance vpn-instance-name ] summary |
Display route attribute information in the RIB. |
display rib attribute [ attribute-id ] |
Display RIB GR state information. |
display rib graceful-restart |
Display next hop information in the RIB. |
display rib nib [ self-originated ] [ nib-id ] [ verbose ] display rib nib protocol protocol [ verbose ] |
Display next hop information for direct routes. |
display route-direct nib [ nib-id ] [ verbose ] |
Clear IPv4 route statistics. |
reset ip routing-table statistics protocol [ vpn-instance vpn-instance-name ] { protocol | all } |
Display IPv6 routing table information. |
display ipv6 routing-table [ vpn-instance vpn-instance-name ] [ verbose ] |
Display information about routes to an IPv6 destination address. |
display ipv6 routing-table [ vpn-instance vpn-instance-name ] ipv6-address [ prefix-length ] [ longer-match ] [ verbose ] |
Display information about routes permitted by an IPv6 basic ACL. |
display ipv6 routing-table [ vpn-instance vpn-instance-name ] acl ipv6-acl-number [ verbose ] |
Display information about routes to a range of IPv6 destination addresses. |
display ipv6 routing-table [ vpn-instance vpn-instance-name ] ipv6-address1 to ipv6-address2 [ verbose ] |
Display information about routes permitted by an IPv6 prefix list. |
display ipv6 routing-table [ vpn-instance vpn-instance-name ] prefix-list prefix-list-name [ verbose ] |
Display information about routes installed by an IPv6 protocol. |
display ipv6 routing-table [ vpn-instance vpn-instance-name ] protocol protocol [ inactive | verbose ] |
Display IPv6 route statistics. |
display ipv6 routing-table [ vpn-instance vpn-instance-name ] statistics |
Display brief IPv6 routing table information. |
display ipv6 routing-table [ vpn-instance vpn-instance-name ] summary |
Display route attribute information in the IPv6 RIB. |
display ipv6 rib attribute [ attribute-id ] |
Display IPv6 RIB GR state information. |
display ipv6 rib graceful-restart |
Display next hop information in the IPv6 RIB. |
display ipv6 rib nib [ self-originated ] [ nib-id ] [ verbose ] display ipv6 rib nib protocol protocol [ verbose ] |
Display next hop information for IPv6 direct routes. |
display ipv6 route-direct nib [ nib-id ] [ verbose ] |
Clear IPv6 route statistics. |
reset ipv6 routing-table statistics protocol [ vpn-instance vpn-instance-name ] { protocol | all } |
Configuring static routing
Static routes are manually configured. If a network's topology is simple, you only need to configure static routes for the network to work correctly.
Static routes cannot adapt to network topology changes. If a fault or a topological change occurs in the network, the network administrator must modify the static routes manually.
Configuring a static route
Before you configure a static route, complete the following tasks:
· Configure the physical parameters for related interfaces.
· Configure the link-layer attributes for related interfaces.
· Configure the IP addresses for related interfaces.
You can associate Track with a static route to monitor the reachability of the next hops. For more information about Track, see High Availability Configuration Guide.
To configure a static route:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. (Optional.) Create a static route group and enter its view. |
ip route-static-group group-name |
By default, no static route group is configured. |
3. (Optional.) Add a static route prefix to the static route group. |
prefix dest-address { mask-length | mask } |
By default, no static route prefix is added to the static route group. |
4. (Optional.) Return to system view. |
quit |
N/A |
5. Configure a static route. |
·
Method 1: ·
Method 2: |
By default, no static route is configured. |
6. (Optional.) Configure the default preference for static routes. |
ip route-static default-preference default-preference |
The default setting is 60. |
7. (Optional.) Delete all static routes, including the default route. |
delete [ vpn-instance vpn-instance-name ] static-routes all |
To delete one static route, use the undo ip route-static command. |
Configuring BFD for static routes
|
IMPORTANT: Enabling BFD for a flapping route could worsen the situation. |
BFD provides a general-purpose, standard, medium-, and protocol-independent fast failure detection mechanism. It can uniformly and quickly detect the failures of the bidirectional forwarding paths between two routers for protocols, such as routing protocols and MPLS.
For more information about BFD, see High Availability Configuration Guide.
Bidirectional control mode
To use BFD bidirectional control detection between two devices, enable BFD control mode for each device's static route destined to the peer.
To configure a static route and enable BFD control mode, use one of the following methods:
· Specify an output interface and a direct next hop.
· Specify an indirect next hop and a specific BFD packet source address for the static route.
To configure BFD control mode for a static route (direct next hop):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Configure BFD control mode for a static route. |
·
Method 1: ·
Method 2: |
By default, BFD control mode for a static route is not configured. |
To configure BFD control mode for a static route (indirect next hop):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Configure BFD control mode for a static route. |
·
Method 1: ·
Method 2: |
By default, BFD control mode for a static route is not configured. |
Single-hop echo mode
With BFD echo mode enabled for a static route, the output interface sends BFD echo packets to the destination device, which loops the packets back to test the link reachability.
|
IMPORTANT: Do not use BFD for a static route with the output interface in spoofing state. |
To configure BFD echo mode for a static route:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Configure the source address of echo packets. |
bfd echo-source-ip ip-address |
By default, the source address of echo packets is not configured. For more information about this command, see High Availability Command Reference. |
3. Configure BFD echo mode for a static route. |
·
Method 1: ·
Method 2: |
By default, BFD echo mode for a static route is not configured. |
Configuring static route FRR
A link or router failure on a path can cause packet loss and even routing loop. Static route fast reroute (FRR) enables fast rerouting to minimize the impact of link or node failures.
As shown in Figure 1, upon a link failure, packets are directed to the backup next hop to avoid traffic interruption. You can either specify a backup next hop for FRR or enable FRR to automatically select a backup next hop (which must be configured in advance).
Configuration guidelines
· Do not use static route FRR and BFD (for a static route) at the same time.
· Static route does not take effect when the backup output interface is unavailable.
· Equal-cost routes do not support static route FRR.
· The backup output interface and next hop must be different from the primary output interface and next hop.
· To change the backup output interface or next hop, you must first remove the current setting.
· Static route FRR is available only when the state of primary link (with Layer 3 interfaces staying up) changes from bidirectional to unidirectional or down.
Configuring static route FRR by specifying a backup next hop
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Configure static route FRR. |
·
Method 1: ·
Method 2: |
By default, static route FRR is disabled. |
Configuring static route FRR to automatically select a backup next hop
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Configure static route FRR to automatically select a backup next hop. |
ip route-static fast-reroute auto |
By default, static route FRR is disabled from automatically selecting a backup next hop. |
Enabling BFD echo packet mode for static route FRR
By default, static route FRR uses ARP to detect primary link failures. Perform this task to enable static route FRR to use BFD echo packet mode for fast failure detection on the primary link.
To enable BFD echo packet mode for static route FRR:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Configure the source IP address of BFD echo packets. |
bfd echo-source-ip ip-address |
By default, the source IP address of BFD echo packets is not configured. The source IP address cannot be on the same network segment as any local interface's IP address. For more information about this command, see High Availability Command Reference. |
3. Enable BFD echo packet mode for static route FRR. |
ip route-static primary-path-detect bfd echo |
By default, BFD echo mode for static route FRR is disabled. |
Displaying and maintaining static routes
Execute display commands in any view.
Task |
Command |
Display static route information. |
display ip routing-table protocol static [ inactive | verbose ] |
Display static route next hop information. |
display route-static nib [ nib-id ] [ verbose ] |
Display static routing table information. |
display route-static routing-table [ vpn-instance vpn-instance-name ] [ ip-address { mask-length | mask } ] |
Static route configuration examples
Basic static route configuration example
Network requirements
As shown in Figure 2, configure static routes on the switches for interconnections between any two hosts.
Configuration procedure
1. Configure IP addresses for interfaces. (Details not shown.)
2. Configure static routes:
# Configure a default route on Switch A.
<SwitchA> system-view
[SwitchA] ip route-static 0.0.0.0 0.0.0.0 1.1.4.2
# Configure two static routes on Switch B.
<SwitchB> system-view
[SwitchB] ip route-static 1.1.2.0 255.255.255.0 1.1.4.1
[SwitchB] ip route-static 1.1.3.0 255.255.255.0 1.1.5.6
# Configure a default route on Switch C.
<SwitchC> system-view
[SwitchC] ip route-static 0.0.0.0 0.0.0.0 1.1.5.5
Verifying the configuration
# Display static routes on Switch A.
[SwitchA] display ip routing-table protocol static
Summary Count : 1
Static Routing table Status : <Active>
Summary Count : 1
Destination/Mask Proto Pre Cost NextHop Interface
0.0.0.0/0 Static 60 0 1.1.4.2 Vlan500
Static Routing table Status : <Inactive>
Summary Count : 0
# Display static routes on Switch B.
[SwitchB] display ip routing-table protocol static
Summary Count : 2
Static Routing table Status : <Active>
Summary Count : 2
Destination/Mask Proto Pre Cost NextHop Interface
1.1.2.0/24 Static 60 0 1.1.4.1 Vlan500
Static Routing table Status : <Inactive>
Summary Count : 0
# Use the ping command on Host B to test the reachability of Host A (Windows XP runs on the two hosts).
C:\Documents and Settings\Administrator>ping 1.1.2.2
Pinging 1.1.2.2 with 32 bytes of data:
Reply from 1.1.2.2: bytes=32 time=1ms TTL=126
Reply from 1.1.2.2: bytes=32 time=1ms TTL=126
Reply from 1.1.2.2: bytes=32 time=1ms TTL=126
Reply from 1.1.2.2: bytes=32 time=1ms TTL=126
Ping statistics for 1.1.2.2:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 1ms, Maximum = 1ms, Average = 1ms
# Use the tracert command on Host B to test the reachability of Host A.
C:\Documents and Settings\Administrator>tracert 1.1.2.2
Tracing route to 1.1.2.2 over a maximum of 30 hops
1 <1 ms <1 ms <1 ms 1.1.6.1
2 <1 ms <1 ms <1 ms 1.1.4.1
3 1 ms <1 ms <1 ms 1.1.2.2
Trace complete.
BFD for static routes configuration example (direct next hop)
Network requirements
Configure the following, as shown in Figure 3:
· Configure a static route to subnet 120.1.1.0/24 on Switch A.
· Configure a static route to subnet 121.1.1.0/24 on Switch B.
· Enable BFD for both routes.
· Configure a static route to subnet 120.1.1.0/24 and a static route to subnet 121.1.1.0/24 on Switch C.
When the link between Switch A and Switch B through the Layer 2 switch fails, BFD can detect the failure immediately. Switch A then communicates with Switch B through Switch C.
Figure 3 Network diagram
Table 4 Interface and IP address assignment
Device |
Interface |
IP address |
Switch A |
VLAN-interface 10 |
12.1.1.1/24 |
Switch A |
VLAN-interface 11 |
10.1.1.102/24 |
Switch B |
VLAN-interface 10 |
12.1.1.2/24 |
Switch B |
VLAN-interface 13 |
13.1.1.1/24 |
Switch C |
VLAN-interface 11 |
10.1.1.100/24 |
Switch C |
VLAN-interface 13 |
13.1.1.2/24 |
Configuration procedure
1. Configure IP addresses for the interfaces. (Details not shown.)
2. Configure static routes and BFD:
# Configure static routes on Switch A and enable BFD control mode for the static route that traverses the Layer 2 switch.
<SwitchA> system-view
[SwitchA] interface vlan-interface 10
[SwitchA-vlan-interface10] bfd min-transmit-interval 500
[SwitchA-vlan-interface10] bfd min-receive-interval 500
[SwitchA-vlan-interface10] bfd detect-multiplier 9
[SwitchA-vlan-interface10] quit
[SwitchA] ip route-static 120.1.1.0 24 vlan-interface 10 12.1.1.2 bfd control-packet
[SwitchA] ip route-static 120.1.1.0 24 vlan-interface 11 10.1.1.100 preference 65
[SwitchA] quit
# Configure static routes on Switch B and enable BFD control mode for the static route that traverses the Layer 2 switch.
<SwitchB> system-view
[SwitchB] interface vlan-interface 10
[SwitchB-vlan-interface10] bfd min-transmit-interval 500
[SwitchB-vlan-interface10] bfd min-receive-interval 500
[SwitchB-vlan-interface10] bfd detect-multiplier 9
[SwitchB-vlan-interface10] quit
[SwitchB] ip route-static 121.1.1.0 24 vlan-interface 10 12.1.1.1 bfd control-packet
[SwitchB] ip route-static 121.1.1.0 24 vlan-interface 13 13.1.1.2 preference 65
[SwitchB] quit
# Configure static routes on Switch C.
<SwitchC> system-view
[SwitchC] ip route-static 120.1.1.0 24 13.1.1.1
[SwitchC] ip route-static 121.1.1.0 24 10.1.1.102
Verifying the configuration
# Display BFD sessions on Switch A.
<SwitchA> display bfd session
Total Session Num: 1 Up Session Num: 1 Init Mode: Active
IPv4 Session Working Under Ctrl Mode:
LD/RD SourceAddr DestAddr State Holdtime Interface
4/7 12.1.1.1 12.1.1.2 Up 2000ms Vlan10
The output shows that the BFD session has been created.
# Display the static routes on Switch A.
<SwitchA> display ip routing-table protocol static
Summary Count : 1
Static Routing table Status : <Active>
Summary Count : 1
Destination/Mask Proto Pre Cost NextHop Interface
120.1.1.0/24 Static 60 0 12.1.1.2 Vlan10
Static Routing table Status : <Inactive>
Summary Count : 0
The output shows that Switch A communicates with Switch B through VLAN-interface 10. Then the link over VLAN-interface 10 fails.
# Display static routes on Switch A.
<SwitchA> display ip routing-table protocol static
Summary Count : 1
Static Routing table Status : <Active>
Summary Count : 1
Destination/Mask Proto Pre Cost NextHop Interface
120.1.1.0/24 Static 65 0 10.1.1.100 Vlan11
Static Routing table Status : <Inactive>
Summary Count : 0
The output shows that Switch A communicates with Switch B through VLAN-interface 11.
BFD for static routes configuration example (indirect next hop)
Network requirements
Figure 4 shows the network topology as follows:
· Switch A has a route to interface Loopback 1 (2.2.2.9/32) on Switch B, with the output interface VLAN-interface 10.
· Switch B has a route to interface Loopback 1 (1.1.1.9/32) on Switch A, with the output interface VLAN-interface 12.
· Switch D has a route to 1.1.1.9/32, with the output interface VLAN-interface 10, and a route to 2.2.2.9/32, with the output interface VLAN-interface 12.
Configure the following:
· Configure a static route to subnet 120.1.1.0/24 on Switch A.
· Configure a static route to subnet 121.1.1.0/24 on Switch B.
· Enable BFD for both routes.
· Configure a static route to subnet 120.1.1.0/24 and a static route to subnet 121.1.1.0/24 on both Switch C and Switch D.
When the link between Switch A and Switch B through Switch D fails, BFD can detect the failure immediately. Switch A then communicates with Switch B through Switch C.
Table 5 Interface and IP address assignment
Device |
Interface |
IP address |
Switch A |
VLAN-interface 10 |
12.1.1.1/24 |
Switch A |
VLAN-interface 11 |
10.1.1.102/24 |
Switch A |
Loopback 1 |
1.1.1.9/32 |
Switch B |
VLAN-interface 12 |
11.1.1.1/24 |
Switch B |
VLAN-interface 13 |
13.1.1.1/24 |
Switch B |
Loopback 1 |
2.2.2.9/32 |
Switch C |
VLAN-interface 11 |
10.1.1.100/24 |
Switch C |
VLAN-interface 13 |
13.1.1.2/24 |
Switch D |
VLAN-interface 10 |
12.1.1.2/24 |
Switch D |
VLAN-interface 12 |
11.1.1.2/24 |
Configuration procedure
1. Configure IP addresses for interfaces. (Details not shown.)
2. Configure static routes and BFD:
# Configure static routes on Switch A and enable BFD control mode for the static route that traverses Switch D.
<SwitchA> system-view
[SwitchA] bfd multi-hop min-transmit-interval 500
[SwitchA] bfd multi-hop min-receive-interval 500
[SwitchA] bfd multi-hop detect-multiplier 9
[SwitchA] ip route-static 120.1.1.0 24 2.2.2.9 bfd control-packet bfd-source 1.1.1.9
[SwitchA] ip route-static 120.1.1.0 24 vlan-interface 11 10.1.1.100 preference 65
[SwitchA] quit
# Configure static routes on Switch B and enable BFD control mode for the static route that traverses Switch D.
<SwitchB> system-view
[SwitchB] bfd multi-hop min-transmit-interval 500
[SwitchB] bfd multi-hop min-receive-interval 500
[SwitchB] bfd multi-hop detect-multiplier 9
[SwitchB] ip route-static 121.1.1.0 24 1.1.1.9 bfd control-packet bfd-source 2.2.2.9
[SwitchB] ip route-static 121.1.1.0 24 vlan-interface 13 13.1.1.2 preference 65
[SwitchB] quit
# Configure static routes on Switch C.
<SwitchC> system-view
[SwitchC] ip route-static 120.1.1.0 24 13.1.1.1
[SwitchC] ip route-static 121.1.1.0 24 10.1.1.102
# Configure static routes on Switch D.
<SwitchD> system-view
[SwitchD] ip route-static 120.1.1.0 24 11.1.1.1
[SwitchD] ip route-static 121.1.1.0 24 12.1.1.1
Verifying the configuration
# Display BFD sessions on Switch A.
<SwitchA> display bfd session
Total Session Num: 1 Up Session Num: 1 Init Mode: Active
IPv4 Session Working Under Ctrl Mode:
LD/RD SourceAddr DestAddr State Holdtime Interface
4/7 1.1.1.9 2.2.2.9 Up 2000ms N/A
The output shows that the BFD session has been created.
# Display the static routes on Switch A.
<SwitchA> display ip routing-table protocol static
Summary Count : 1
Static Routing table Status : <Active>
Summary Count : 1
Destination/Mask Proto Pre Cost NextHop Interface
120.1.1.0/24 Static 60 0 12.1.1.2 Vlan10
Static Routing table Status : <Inactive>
Summary Count : 0
The output shows that Switch A communicates with Switch B through VLAN-interface 10. Then the link over VLAN-interface 10 fails.
# Display static routes on Switch A.
<SwitchA> display ip routing-table protocol static
Summary Count : 1
Static Routing table Status : <Active>
Summary Count : 1
Destination/Mask Proto Pre Cost NextHop Interface
120.1.1.0/24 Static 65 0 10.1.1.100 Vlan11
Static Routing table Status : <Inactive>
Summary Count : 0
The output shows that Switch A communicates with Switch B through VLAN-interface 11.
Static route FRR configuration example
Network requirements
As shown in Figure 5, configure static routes on Switch A, Switch B, and Switch C, and configure static route FRR. When Link A becomes unidirectional, traffic can be switched to Link B immediately.
Table 6 Interface and IP address assignment
Device |
Interface |
IP address |
Switch A |
VLAN-interface 100 |
12.12.12.1/24 |
Switch A |
VLAN-interface 200 |
13.13.13.1/24 |
Switch A |
Loopback 0 |
1.1.1.1/32 |
Switch B |
VLAN-interface 101 |
24.24.24.4/24 |
Switch B |
VLAN-interface 200 |
13.13.13.2/24 |
Switch B |
Loopback 0 |
4.4.4.4/32 |
Switch C |
VLAN-interface 100 |
12.12.12.2/24 |
Switch C |
VLAN-interface 101 |
24.24.24.2/24 |
Configuration procedure
1. Configure IP addresses for interfaces. (Details not shown.)
2. Configure static route FRR on link A by using one of the following methods:
? (Method 1.) Specify a backup next hop for static route FRR:
# Configure a static route on Switch A, and specify VLAN-interface 100 as the backup output interface and 12.12.12.2 as the backup next hop.
<SwitchA> system-view
[SwitchA] ip route-static 4.4.4.4 32 vlan-interface 200 13.13.13.2 backup-interface vlan-interface 100 backup-nexthop 12.12.12.2
# Configure a static route on Switch B, and specify VLAN-interface 101 as the backup output interface and 24.24.24.2 as the backup next hop.
<SwitchB> system-view
[SwitchB] ip route-static 1.1.1.1 32 vlan-interface 200 13.13.13.1 backup-interface vlan-interface 101 backup-nexthop 24.24.24.2
? (Method 2.) Configure static route FRR to automatically select a backup next hop:
# Configure static routes on Switch A, and enable static route FRR.
<SwitchA> system-view
[SwitchA] ip route-static 4.4.4.4 32 vlan-interface 200 13.13.13.2
[SwitchA] ip route-static 4.4.4.4 32 vlan-interface 100 12.12.12.2 preference 70
[SwitchA] ip route-static fast-reroute auto
# Configure static routes on Switch B, and enable static route FRR.
<SwitchB> system-view
[SwitchB] ip route-static 1.1.1.1 32 vlan-interface 200 13.13.13.1
[SwitchB] ip route-static 1.1.1.1 32 vlan-interface 101 24.24.24.2 preference 70
[SwitchB] ip route-static fast-reroute auto
3. Configure static routes on Switch C.
<SwitchC> system-view
[SwitchC] ip route-static 4.4.4.4 32 vlan-interface 101 24.24.24.4
[SwitchC] ip route-static 1.1.1.1 32 vlan-interface 100 12.12.12.1
Verifying the configuration
# Display route 4.4.4.4/32 on Switch A to view the backup next hop information.
[SwitchA] display ip routing-table 4.4.4.4 verbose
Summary Count : 1
Destination: 4.4.4.4/32
Protocol: Static
Process ID: 0
SubProtID: 0x0 Age: 04h20m37s
Cost: 0 Preference: 60
IpPre: N/A QosLocalID: N/A
Tag: 0 State: Active Adv
OrigTblID: 0x0 OrigVrf: default-vrf
TableID: 0x2 OrigAs: 0
NibID: 0x26000002 LastAs: 0
AttrID: 0xffffffff Neighbor: 0.0.0.0
Flags: 0x1008c OrigNextHop: 13.13.13.2
Label: NULL RealNextHop: 13.13.13.2
BkLabel: NULL BkNextHop: 12.12.12.2
Tunnel ID: Invalid Interface: Vlan-interface200
BkTunnel ID: Invalid BkInterface: Vlan-interface100
FtnIndex: 0x0 TrafficIndex: N/A
Connector: N/A
# Display route 1.1.1.1/32 on Switch B to view the backup next hop information.
[SwitchB] display ip routing-table 1.1.1.1 verbose
Summary Count : 1
Destination: 1.1.1.1/32
Protocol: Static
Process ID: 0
SubProtID: 0x0 Age: 04h20m37s
Cost: 0 Preference: 60
IpPre: N/A QosLocalID: N/A
Tag: 0 State: Active Adv
OrigTblID: 0x0 OrigVrf: default-vrf
TableID: 0x2 OrigAs: 0
NibID: 0x26000002 LastAs: 0
AttrID: 0xffffffff Neighbor: 0.0.0.0
Flags: 0x1008c OrigNextHop: 13.13.13.1
Label: NULL RealNextHop: 13.13.13.1
BkLabel: NULL BkNextHop: 24.24.24.2
Tunnel ID: Invalid Interface: Vlan-interface200
BkTunnel ID: Invalid BkInterface: Vlan-interface101
FtnIndex: 0x0 TrafficIndex: N/A
Connector: N/A
Configuring a default route
A default route is used to forward packets that do not match any specific routing entry in the routing table. Without a default route, packets that do not match any routing entries are discarded.
A default route can be configured in either of the following ways:
· The network administrator can configure a default route with both destination and mask being 0.0.0.0. For more information, see "Configuring static routing."
· Some dynamic routing protocols, such as OSPF, IS-IS, and RIP, can generate a default route. For example, an upstream router running OSPF can generate a default route and advertise it to other routers. These routers install the default route with the next hop being the upstream router. For more information, see the respective chapters on these routing protocols in this configuration guide.
Configuring RIP
Overview
Routing Information Protocol (RIP) is a distance-vector IGP suited to small-sized networks. It employs UDP to exchange route information through port 520.
RIP uses a hop count to measure the distance to a destination. The hop count from a router to a directly connected network is 0. The hop count from a router to a directly connected router is 1. To limit convergence time, RIP restricts the value range of the metric from 0 to 15. A destination with a metric value of 16 (or greater) is considered unreachable. For this reason, RIP is not suitable for large-sized networks.
RIP route entries
RIP stores routing entries in a database. Each routing entry contains the following elements:
· Destination address—IP address of a destination host or a network.
· Next hop—IP address of the next hop.
· Egress interface—Egress interface of the route.
· Metric—Cost from the local router to the destination.
· Route time—Time elapsed since the last update. The time is reset to 0 when the routing entry is updated.
· Route tag—Used for route control. For more information, see "Configuring routing policies."
Routing loop prevention
RIP uses the following mechanisms to prevent routing loops:
· Counting to infinity—A destination with a metric value of 16 is considered unreachable. When a routing loop occurs, the metric value of a route will increment to 16 to avoid endless looping.
· Triggered updates—RIP immediately advertises triggered updates for topology changes to reduce the possibility of routing loops and to speed up convergence.
· Split horizon—Disables RIP from sending routes through the interface where the routes were learned to prevent routing loops and save bandwidth.
· Poison reverse—Enables RIP to set the metric of routes received from a neighbor to 16 and sends these routes back to the neighbor. The neighbor can delete such information from its routing table to prevent routing loops.
RIP operation
RIP works as follows:
1. RIP sends request messages to neighboring routers. Neighboring routers return response messages that contain their routing tables.
2. RIP uses the received responses to update the local routing table and sends triggered update messages to its neighbors. All RIP routers on the network do this to learn latest routing information.
3. RIP periodically sends the local routing table to its neighbors. After a RIP neighbor receives the message, it updates its routing table, selects optimal routes, and sends an update to other neighbors. RIP ages routes to keep only valid routes.
RIP versions
There are two RIP versions, RIPv1 and RIPv2.
RIPv1 is a classful routing protocol. It advertises messages only through broadcast. RIPv1 messages do not carry mask information, so RIPv1 can only recognize natural networks such as Class A, B, and C. For this reason, RIPv1 does not support discontiguous subnets.
RIPv2 is a classless routing protocol. It has the following advantages over RIPv1:
· Supports route tags to implement flexible route control through routing policies.
· Supports masks, route summarization, and CIDR.
· Supports designated next hops to select the best ones on broadcast networks.
· Supports multicasting route updates so only RIPv2 routers can receive these updates to reduce resource consumption.
· Supports plain text authentication and MD5 authentication to enhance security.
RIPv2 supports two transmission modes: broadcast and multicast. Multicast is the default mode using 224.0.0.9 as the multicast address. An interface operating in RIPv2 broadcast mode can also receive RIPv1 messages.
Protocols and standards
· RFC 1058, Routing Information Protocol
· RFC 1723, RIP Version 2 - Carrying Additional Information
· RFC 1721, RIP Version 2 Protocol Analysis
· RFC 1722, RIP Version 2 Protocol Applicability Statement
· RFC 1724, RIP Version 2 MIB Extension
· RFC 2082, RIPv2 MD5 Authentication
RIP configuration task list
Configuring basic RIP
Before you configure basic RIP settings, complete the following tasks:
· Configure the link layer protocol.
· Configure IP addresses for interfaces to ensure IP connectivity between neighboring routers.
Enabling RIP
Follow these guidelines when you enable RIP:
· To enable multiple RIP processes on a router, you must specify an ID for each process. A RIP process ID has only local significance. Two RIP routers having different process IDs can also exchange RIP packets.
· If you configure RIP settings in interface view before enabling RIP, the settings do not take effect until RIP is enabled.
· If a physical interface is attached to multiple networks, you cannot advertise these networks in different RIP processes.
· You cannot enable multiple RIP processes on a physical interface.
· The rip enable command takes precedence over the network command.
Enabling RIP on a network
You can enable RIP on a network and specify a wildcard mask for the network. After that, only the interface attached to the network runs RIP.
To enable RIP on a network:
Command |
Remarks |
|
1. Enter system view. |
system-view |
N/A |
2. Enable RIP and enter RIP view. |
rip [ process-id ] [ vpn-instance vpn-instance-name ] |
By default, RIP is disabled. |
3. Enable RIP on a network. |
network network-address [ wildcard-mask ] |
By default, RIP is disabled on a network. The network 0.0.0.0 command can enable RIP on all interfaces in a single process, but does not apply to multiple RIP processes. |
Enabling RIP on an interface
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enable RIP and enter RIP view. |
rip [ process-id ] [ vpn-instance vpn-instance-name ] |
By default, RIP is disabled. |
3. Return to system view. |
quit |
N/A |
4. Enter interface view. |
interface interface-type interface-number |
N/A |
5. Enable RIP on the interface. |
rip process-id enable [ exclude-subip ] |
By default, RIP is disabled on an interface. |
Controlling RIP reception and advertisement on interfaces
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIP view. |
rip [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Disable an interface from sending RIP messages. |
silent-interface { interface-type interface-number | all } |
By default, all RIP-enabled interfaces can send RIP messages. The disabled interface can still receive RIP messages and respond to unicast requests containing unknown ports. |
4. Return to system view. |
quit |
N/A |
5. Enter interface view. |
interface interface-type interface-number |
N/A |
6. Enable an interface to receive RIP messages. |
rip input |
By default, a RIP-enabled interface can receive RIP messages. |
7. Enable an interface to send RIP messages. |
rip output |
By default, a RIP-enabled interface can send RIP messages. |
Configuring a RIP version
You can configure a global RIP version in RIP view or an interface-specific RIP version in interface view.
An interface preferentially uses the interface-specific RIP version. If no interface-specific version is specified, the interface uses the global RIP version. If neither a global nor interface-specific RIP version is configured, the interface sends RIPv1 broadcasts and can receive the following:
· RIPv1 broadcasts and unicasts.
· RIPv2 broadcasts, multicasts, and unicasts.
To configure a RIP version:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIP view. |
rip [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Specify a global RIP version. |
version { 1 | 2 } |
By default, no global version is specified. An interface sends RIPv1 broadcasts, and can receive RIPv1 broadcasts and unicasts, and RIPv2 broadcasts, multicasts, and unicasts. |
4. Return to system view. |
quit |
N/A |
5. Enter interface view. |
interface interface-type interface-number |
N/A |
6. Specify a RIP version for the interface. |
rip version { 1 | 2 [ broadcast | multicast ] } |
By default, no interface-specific RIP version is specified. The interface sends RIPv1 broadcasts, and can receive RIPv1 broadcasts and unicasts, and RIPv2 broadcasts, multicasts, and unicasts. |
Configuring RIP route control
Before you configure RIP route control, complete the following tasks:
· Configure IP addresses for interfaces to ensure IP connectivity between neighboring routers.
· Configure basic RIP.
Configuring an additional routing metric
An additional routing metric (hop count) can be added to the metric of an inbound or outbound RIP route.
An outbound additional metric is added to the metric of a sent route, and it does not change the route's metric in the routing table.
An inbound additional metric is added to the metric of a received route before the route is added into the routing table, and the route's metric is changed. If the sum of the additional metric and the original metric is greater than 16, the metric of the route is 16.
To configure additional routing metrics:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Specify an inbound additional routing metric. |
rip metricin [ route-policy route-policy-name ] value |
The default setting is 0. |
4. Specify an outbound additional routing metric. |
rip metricout [ route-policy route-policy-name ] value |
The default setting is 1. |
Configuring RIPv2 route summarization
Perform this task to summarize contiguous subnets into a summary network and sends the network to neighbors. The smallest metric among all summarized routes is used as the metric of the summary route.
Enabling RIPv2 automatic route summarization
Automatic summarization enables RIPv2 to generate a natural network for contiguous subnets. For example, suppose there are three subnet routes 10.1.1.0/24, 10.1.2.0/24, and 10.1.3.0/24. Automatic summarization automatically creates and advertises a summary route 10.0.0.0/8 instead of the more specific routes.
To enable RIPv2 automatic route summarization:
Command |
Remarks |
|
1. Enter system view. |
system-view |
N/A |
2. Enter RIP view. |
rip [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. (Optional.) Enable RIPv2 automatic route summarization. |
summary |
By default, RIPv2 automatic route summarization is enabled. If subnets in the routing table are not contiguous, disable automatic route summarization to advertise more specific routes. |
Advertising a summary route
Perform this task to manually configure a summary route.
For example, suppose contiguous subnets routes 10.1.1.0/24, 10.1.2.0/24, and 10.1.3.0/24 exist in the routing table. You can create a summary route 10.1.0.0/16 on HundredGigE 1/0/1 to advertise the summary route instead of the more specific routes.
To configure a summary route:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIP view. |
rip [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Disable RIPv2 automatic route summarization. |
undo summary |
By default, RIPv2 automatic route summarization is enabled. |
4. Return to system view. |
quit |
N/A |
5. Enter interface view. |
interface interface-type interface-number |
N/A |
6. Configure a summary route. |
rip summary-address ip-address { mask-length | mask } |
By default, no summary route is configured. |
Disabling host route reception
Perform this task to disable RIPv2 from receiving host routes from the same network to save network resources. This feature does not apply to RIPv1.
To disable RIP from receiving host routes:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIP view. |
rip [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Disable RIP from receiving host routes. |
undo host-route |
By default, RIP receives host routes. |
Advertising a default route
You can advertise a default route on all RIP interfaces in RIP view or on a specific RIP interface in interface view. The interface view setting takes precedence over the RIP view settings.
To disable an interface from advertising a default route, use the rip default-route no-originate command on the interface.
To configure RIP to advertise a default route:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIP view. |
rip [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Enable RIP to advertise a default route. |
default-route { only | originate } [ cost cost-value | route-policy route-policy-name ] * |
By default, RIP does not advertise a default route. |
4. Return to system view. |
quit |
N/A |
5. Enter interface view. |
interface interface-type interface-number |
N/A |
6. Configure the RIP interface to advertise a default route. |
rip default-route { { only | originate } [ cost cost-value | route-policy route-policy-name ] * | no-originate } |
By default, a RIP interface can advertise a default route if the RIP process is enabled to advertise a default route. |
|
NOTE: The router enabled to advertise a default route does not accept default routes from RIP neighbors. |
Configuring received/redistributed route filtering
Perform this task to filter received and redistributed routes by using a filtering policy.
To configure route filtering:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIP view. |
rip [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Configure the filtering of received routes. |
filter-policy { ipv4-acl-number | gateway prefix-list-name | prefix-list prefix-list-name [ gateway prefix-list-name ] } import [ interface-type interface-number ] |
By default, the filtering of received routes is not configured. This command filters received routes. Filtered routes are not installed into the routing table or advertised to neighbors. |
4. Configure the filtering of redistributed routes. |
filter-policy { ipv4-acl-number | prefix-list prefix-list-name } export [ protocol [ process-id ] | interface-type interface-number ] |
By default, the filtering of redistributed routes is not configured. This command filters redistributed routes, including routes redistributed with the import-route command. |
Setting a preference for RIP
If multiple IGPs find routes to the same destination, the route found by the IGP that has the highest priority is selected as the optimal route. Perform this task to assign a preference to RIP. The smaller the preference value, the higher the priority.
To set a preference for RIP:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIP view. |
rip [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Set a preference for RIP. |
preference { preference | route-policy route-policy-name } * |
The default setting is 100. |
Configuring RIP route redistribution
Perform this task to configure RIP to redistribute routes from other routing protocols, including OSPF, IS-IS, BGP, static, and direct.
To configure RIP route redistribution:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIP view. |
rip [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Redistribute routes from another routing protocol. |
import-route protocol [ as-number ] [ process-id | all-processes | allow-ibgp ] [ allow-direct | cost cost-value | route-policy route-policy-name | tag tag ] * |
By default, RIP route redistribution is disabled. This command can redistribute only active routes. To view active routes, use the display ip routing-table protocol command. |
4. (Optional.) Set a default cost for redistributed routes. |
default cost cost-value |
The default setting is 0. |
Tuning and optimizing RIP networks
Configuration prerequisites
Before you tune and optimize RIP networks, complete the following tasks:
· Configure IP addresses for interfaces to ensure IP connectivity between neighboring nodes.
· Configure basic RIP.
Setting RIP timers
You can change the RIP network convergence speed by adjusting the following RIP timers:
· Update timer—Specifies the interval between route updates.
· Timeout timer—Specifies the route aging time. If no update for a route is received within the aging time, the metric of the route is set to 16.
· Suppress timer—Specifies how long a RIP route stays in suppressed state. When the metric of a route is 16, the route enters the suppressed state. A suppressed route can be replaced by an updated route that is received from the same neighbor before the suppress timer expires and has a metric less than 16.
· Garbage-collect timer—Specifies the interval from when the metric of a route becomes 16 to when it is deleted from the routing table. RIP advertises the route with a metric of 16. If no update is announced for that route before the garbage-collect timer expires, the route is deleted from the routing table.
|
IMPORTANT: To avoid unnecessary traffic or route flapping, configure identical RIP timer settings on RIP routers. |
To set RIP timers:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIP view. |
rip [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Set RIP timers. |
timers { garbage-collect garbage-collect-value | suppress suppress-value | timeout timeout-value | update update-value } * |
By default: · The garbage-collect timer is 120 seconds. · The suppress timer is 120 seconds. · The timeout timer is 180 seconds. · The update timer is 30 seconds. |
Enabling split horizon and poison reverse
The split horizon and poison reverse functions can prevent routing loops.
If both split horizon and poison reverse are configured, only the poison reverse function takes effect.
Enabling split horizon
Split horizon disables RIP from sending routes through the interface where the routes were learned to prevent routing loops between adjacent routers.
To enable split horizon:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Enable split horizon. |
rip split-horizon |
By default, split horizon is enabled. |
Enabling poison reverse
Poison reverse allows RIP to send routes through the interface where the routes were learned. The metric of these routes is always set to 16 (unreachable) to avoid routing loops between neighbors.
To enable poison reverse:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Enable poison reverse. |
rip poison-reverse |
By default, poison reverse is disabled. |
Setting the maximum number of RIP ECMP routes
Perform this task to implement load sharing over ECMP routes.
To set the maximum number of RIP ECMP routes:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIP view. |
rip [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Set the maximum number of RIP ECMP routes. |
maximum load-balancing number |
By default, the maximum number of RIP ECMP routes equals the maximum number of ECMP routes supported by the system. |
Enabling zero field check on incoming RIPv1 messages
Some fields in the RIPv1 message must be set to zero. These fields are called "zero fields." You can enable zero field check on incoming RIPv1 messages. If a zero field of a message contains a non-zero value, RIP does not process the message. If you are certain that all messages are trustworthy, disable zero field check to save CPU resources.
This feature does not apply to RIPv2 packets, because they have no zero fields.
To enable zero field check on incoming RIPv1 messages:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIP view. |
rip [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Enable zero field check on incoming RIPv1 messages. |
checkzero |
The default setting is enabled. |
Enabling source IP address check on incoming RIP updates
Perform this task to enable source IP address check on incoming RIP updates.
Upon receiving a message on an Ethernet interface, RIP compares the source IP address of the message with the IP address of the interface. If they are not in the same network segment, RIP discards the message.
Upon receiving a message on a PPP interface, RIP checks whether the source address of the message is the IP address of the peer interface. If not, RIP discards the message.
To enable source IP address check on incoming RIP updates:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIP view. |
rip [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Enable source IP address check on incoming RIP messages. |
validate-source-address |
By default, this function is enabled. |
Configuring RIPv2 message authentication
Perform this task to enable authentication on RIPv2 messages. This feature does not apply to RIPv1 because RIPv1 does not support authentication. Although you can specify an authentication mode for RIPv1 in interface view, the configuration does not take effect.
RIPv2 supports two authentication modes: simple authentication and MD5 authentication.
To configure RIPv2 message authentication:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Configure RIPv2 authentication. |
rip authentication-mode { md5 { rfc2082 { cipher | plain } string key-id | rfc2453 { cipher | plain } string } | simple { cipher | plain } string } |
By default, RIPv2 authentication is not configured. |
Setting the RIP triggered update interval
Perform this task to avoid network overhead and reduce system resource consumption caused by frequent RIP triggered updates.
You can use the timer triggered command to set the maximum interval, minimum interval, and incremental interval for sending RIP triggered updates.
· For a stable network, the minimum-interval is used.
· If network changes become frequent, the incremental interval incremental-interval is used to extend the triggered update sending interval until the maximum-interval is reached.
To set the triggered update interval:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIP view. |
rip [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Set the RIP triggered update interval. |
timer triggered maximum-interval [ minimum-interval [ incremental-interval ] ] |
By default: · The maximum interval is 5 seconds. · The minimum interval is 50 milliseconds. · The incremental interval is 200 milliseconds. |
Specifying a RIP neighbor
Typically RIP messages are sent in broadcast or multicast. To enable RIP on a link that does not support broadcast or multicast, you must manually specify RIP neighbors.
Follow these guidelines when you specify a RIP neighbor:
· Do not use the peer ip-address command when the neighbor is directly connected. Otherwise, the neighbor might receive both unicast and multicast (or broadcast) messages of the same routing information.
· If the specified neighbor is not directly connected, disable source address check on incoming updates.
To specify a RIP neighbor:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIP view. |
rip [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Specify a RIP neighbor. |
peer ip-address |
By default, RIP does not unicast updates to any peer. |
4. Disable source IP address check on inbound RIP updates |
undo validate-source-address |
By default, source IP address check on inbound RIP updates is enabled. |
Configuring RIP network management
You can use network management software to manage the RIP process to which MIB is bound.
To configure RIP network management:
Command |
Remarks |
|
1. Enter system view. |
system-view |
N/A |
2. Bind MIB to a RIP process. |
rip mib-binding process-id |
By default, MIB is bound to the RIP process with the smallest process ID. |
Configuring the RIP packet sending rate
Perform this task to set the interval for sending RIP packets and the maximum number of RIP packets that can be sent at each interval. This feature can avoid excessive RIP packets from affecting system performance and consuming too much bandwidth.
To configure the RIP packet sending rate:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIP view. |
rip [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Set the interval for sending RIP packets and the maximum number of RIP packets that can be sent at each interval. |
output-delay time count count |
By default, an interface sends up to three RIP packets every 20 milliseconds. |
4. Return to system view. |
quit |
N/A |
5. Enter interface view. |
interface interface-type interface-number |
N/A |
6. Set the interval for sending RIP packets and the maximum number of RIP packets that can be sent at each interval. |
rip output-delay time count count |
By default, the interface uses the RIP packet sending rate configured for the RIP process that the interface runs. |
Setting the maximum length of RIP packets
|
CAUTION: The supported maximum length of RIP packets varies by vendor. Use this feature with caution to avoid compatibility issues. |
The packet length of RIP packets determines how many routes can be carried in a RIP packet. Set the maximum length of RIP packets to make good use of link bandwidth.
When authentication is enabled, follow these guidelines to ensure packet forwarding:
· For simple authentication, the maximum length of RIP packets must be no less than 52 bytes.
· For MD5 authentication (with packet format defined in RFC 2453), the maximum length of RIP packets must be no less than 56 bytes.
· For MD5 authentication (with packet format defined in RFC 2082), the maximum length of RIP packets must be no less than 72 bytes.
To set the maximum length of RIP packets:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Set the maximum length of RIP packets. |
rip max-packet-length value |
By default, the maximum length of RIP packets is 512 bytes. |
Setting the DSCP value for outgoing RIP packets
The DSCP value specifies the precedence of outgoing packets.
To set the DSCP value for outgoing RIP packets:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIP view. |
rip [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Set the DSCP value for outgoing RIP packets. |
dscp dscp-value |
By default, the DSCP value for outgoing RIP packets is 48. |
Configuring RIP GR
GR ensures forwarding continuity when a routing protocol restarts or an active/standby switchover occurs.
Two routers are required to complete a GR process. The following are router roles in a GR process:
· GR restarter—Graceful restarting router. It must have GR capability.
· GR helper—A neighbor of the GR restarter. It helps the GR restarter to complete the GR process.
After RIP restarts on a router, the router must learn RIP routes again and update its FIB table, which causes network disconnections and route reconvergence.
With the GR feature, the restarting router (known as the GR restarter) can notify the event to its GR capable neighbors. GR capable neighbors (known as GR helpers) maintain their adjacencies with the router within a GR interval. During this process, the FIB table of the router does not change. After the restart, the router contacts its neighbors to retrieve its FIB.
By default, a RIP-enabled device acts as the GR helper. Perform this task on the GR restarter.
|
IMPORTANT: You cannot enable RIP NSR on a device that acts as GR restarter. |
To configure GR on the GR restarter:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIP view. |
rip [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Enable GR for RIP. |
graceful-restart |
By default, RIP GR is disabled. |
4. (Optional.) Set the GR interval. |
graceful-restart interval interval |
By default, the GR interval is 60 seconds. |
Enabling RIP NSR
NSR does not require the cooperation of neighboring devices to recover routing information, and it is typically used more often than GR.
|
IMPORTANT: A device that has RIP NSR enabled cannot act as GR restarter. |
To enable RIP NSR:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIP view. |
rip [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Enable RIP NSR. |
non-stop-routing |
By default, RIP NSR is disabled. RIP NSR enabled for a RIP process takes effect only on that process. As a best practice, enable RIP NSR for each process if multiple RIP processes exist. |
Configuring BFD for RIP
RIP detects route failures by periodically sending requests. If it receives no response for a route within a certain time, RIP considers the route unreachable. To speed up convergence, perform this task to enable BFD for RIP. For more information about BFD, see High Availability Configuration Guide.
RIP supports the following BFD detection modes:
· Single-hop echo detection—Detection mode for a direct neighbor. In this mode, a BFD session is established only when the directly connected neighbor has route information to send.
· Single-hop echo detection for a specific destination—In this mode, a BFD session is established to the specified RIP neighbor when RIP is enabled on the local interface.
· Bidirectional control detection—Detection mode for an indirect neighbor. In this mode, a BFD session is established only when both ends have routes to send and BFD is enabled on the receiving interface.
Configuring single-hop echo detection (for a directly connected RIP neighbor)
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Configure the source IP address of BFD echo packets. |
bfd echo-source-ip ip-address |
By default, the source IP address of BFD echo packets is not configured. |
3. Enter interface view. |
interface interface-type interface-number |
N/A |
4. Enable BFD for RIP. |
rip bfd enable |
By default, BFD for RIP is disabled. |
Configuring single-hop echo detection (for a specific destination)
When a unidirectional link occurs between the local device and a specific neighbor, BFD can detect the failure. The local device will not receive or send any RIP packets through the interface connected to the neighbor to improve convergence speed. When the link recovers, the interface can send RIP packets again.
This feature applies to RIP neighbors that are directly connected.
To configure BFD for RIP (single hop echo detection for a specific destination):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Configure the source IP address of BFD echo packets. |
bfd echo-source-ip ip-address |
By default, no source IP address is configured for BFD echo packets. |
3. Enter interface view. |
interface interface-type interface-number |
N/A |
4. Enable BFD for RIP. |
rip bfd enable destination ip-address |
By default, BFD for RIP is disabled. |
Configuring bidirectional control detection
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIP view. |
rip [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Specify a RIP neighbor. |
peer ip-address |
By default, RIP does not unicast updates to any peer. Because the undo peer command does not remove the neighbor relationship immediately, executing the command cannot bring down the BFD session immediately. |
4. Enter interface view. |
interface interface-type interface-number |
N/A |
5. Enable BFD on the RIP interface. |
rip bfd enable |
By default, BFD is disabled on a RIP interface. |
Configuring RIP FRR
A link or router failure on a path can cause packet loss and even routing loop until RIP completes routing convergence based on the new network topology. FRR enables fast rerouting to minimize the impact of link or node failures.
Figure 6 Network diagram for RIP FRR
As shown in Figure 6, configure FRR on Router B by using a routing policy to specify a backup next hop. When the primary link fails, RIP directs packets to the backup next hop. At the same time, RIP calculates the shortest path based on the new network topology, and forwards packets over that path after network convergence.
Configuration restrictions and guidelines
· RIP FRR takes effect only for RIP routes learned from directly connected neighbors.
· RIP FRR is available only when the state of primary link (with Layer 3 interfaces staying up) changes from bidirectional to unidirectional or down.
· Equal-cost routes do not support RIP FRR.
Configuration prerequisites
You must specify a next hop by using the apply fast-reroute backup-interface command in a routing policy and reference the routing policy for FRR. For more information about routing policy configuration, see "Configuring routing policies."
Configuring RIP FRR
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIP view. |
rip [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Configure RIP FRR. |
fast-reroute route-policy route-policy-name |
By default, RIP FRR is disabled. |
Enabling BFD for RIP FRR
By default, RIP FRR does not use BFD to detect primary link failures. To speed up RIP convergence, enable BFD single-hop echo detection for RIP FRR to detect primary link failures.
To configure BFD for RIP FRR:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Configure the source IP address of BFD echo packets. |
bfd echo-source-ip ip-address |
By default, the source IP address of BFD echo packets is not configured. The source IP address cannot be on the same network segment as any local interface's IP address. For more information about this command, see High Availability Command Reference. |
3. Enter interface view. |
interface interface-type interface-number |
N/A |
4. Enable BFD for RIP FRR. |
rip primary-path-detect bfd echo |
By default, BFD for RIP FRR is disabled. |
Displaying and maintaining RIP
Execute display commands in any view and execute reset commands in user view.
Command |
|
Display RIP current status and configuration information. |
display rip [ process-id ] |
Display active routes in the RIP database. |
display rip process-id database [ ip-address { mask-length | mask } ] |
Display RIP GR information. |
display rip [ process-id ] graceful-restart |
Display RIP interface information. |
display rip process-id interface [ interface-type interface-number ] |
Display neighbor information for a RIP process. |
display rip process-id neighbor [ interface-type interface-number ] |
Display RIP NSR information. |
display rip [ process-id ] non-stop-routing |
Display routing information for a RIP process. |
display rip process-id route [ ip-address { mask-length | mask } [ verbose ] | peer ip-address | statistics ] |
Reset a RIP process. |
reset rip process-id process |
Clear the statistics for a RIP process. |
reset rip process-id statistics |
RIP configuration examples
Configuring basic RIP
Network requirements
As shown in Figure 7, enable RIPv2 on all interfaces on Switch A and Switch B. Configure Switch B to not advertise route 10.2.1.0/24 to Switch A, and to accept only route 2.1.1.0/24 from Switch A.
Configuration procedure
1. Configure IP addresses for interfaces. (Details not shown.)
2. Configure basic RIP by using either of the following methods:
(Method 1) # Enable RIP on the specified networks on Switch A.
<SwitchA> system-view
[SwitchA] rip
[SwitchA-rip-1] network 1.0.0.0
[SwitchA-rip-1] network 2.0.0.0
[SwitchA-rip-1] network 3.0.0.0
[SwitchA-rip-1] quit
(Method 2) # Enable RIP on the specified interfaces on Switch B.
<SwitchB> system-view
[SwitchB] rip
[SwitchB-rip-1] quit
[SwitchB] interface vlan-interface 100
[SwitchB-Vlan-interface100] rip 1 enable
[SwitchB-Vlan-interface100] quit
[SwitchB] interface vlan-interface 101
[SwitchB-Vlan-interface101] rip 1 enable
[SwitchB-Vlan-interface101] quit
[SwitchB] interface vlan-interface 102
[SwitchB-Vlan-interface102] rip 1 enable
[SwitchB-Vlan-interface102] quit
# Display the RIP routing table of Switch A.
[SwitchA] display rip 1 route
Route Flags: R - RIP, T - TRIP
P - Permanent, A - Aging, S - Suppressed, G - Garbage-collect
D - Direct, O - Optimal, F - Flush to RIB
----------------------------------------------------------------------------
Peer 1.1.1.2 on Vlan-interface100
Destination/Mask Nexthop Cost Tag Flags Sec
10.0.0.0/8 1.1.1.2 1 0 RAOF 11
Local route
Destination/Mask Nexthop Cost Tag Flags Sec
1.1.1.0/24 0.0.0.0 0 0 RDOF -
2.1.1.0/24 0.0.0.0 0 0 RDOF -
3.1.1.0/24 0.0.0.0 0 0 RDOF -
The output shows that RIPv1 uses a natural mask.
3. Configure a RIP version:
# Configure RIPv2 on Switch A.
[SwitchA] rip
[SwitchA-rip-1] version 2
[SwitchA-rip-1] undo summary
[SwitchA-rip-1] quit
# Configure RIPv2 on Switch B.
[SwitchB] rip
[SwitchB-rip-1] version 2
[SwitchB-rip-1] undo summary
[SwitchB-rip-1] quit
# Display the RIP routing table on Switch A.
[SwitchA] display rip 1 route
Route Flags: R - RIP, T - TRIP
P - Permanent, A - Aging, S - Suppressed, G - Garbage-collect
D - Direct, O - Optimal, F - Flush to RIB
----------------------------------------------------------------------------
Peer 1.1.1.2 on Vlan-interface100
Destination/Mask Nexthop Cost Tag Flags Sec
10.0.0.0/8 1.1.1.2 1 0 RAOF 50
10.2.1.0/24 1.1.1.2 1 0 RAOF 16
10.1.1.0/24 1.1.1.2 1 0 RAOF 16
Local route
Destination/Mask Nexthop Cost Tag Flags Sec
1.1.1.0/24 0.0.0.0 0 0 RDOF -
2.1.1.0/24 0.0.0.0 0 0 RDOF -
3.1.1.0/24 0.0.0.0 0 0 RDOF -
The output shows that RIPv2 uses classless subnet masks.
|
NOTE: After RIPv2 is configured, RIPv1 routes might still exist in the routing table until they are aged out. |
# Display the RIP routing table on Switch B.
[SwitchB] display rip 1 route
Route Flags: R - RIP, T - TRIP
P - Permanent, A - Aging, S - Suppressed, G - Garbage-collect
D - Direct, O - Optimal, F - Flush to RIB
----------------------------------------------------------------------------
Peer 1.1.1.1 on Vlan-interface100
Destination/Mask Nexthop Cost Tag Flags Sec
2.1.1.0/24 192.168.1.3 1 0 RAOF 19
3.1.1.0/24 192.168.1.3 1 0 RAOF 19
Local route
Destination/Mask Nexthop Cost Tag Flags Sec
1.1.1.0/24 0.0.0.0 0 0 RDOF -
10.1.1.0/24 0.0.0.0 0 0 RDOF -
10.2.1.0/24 0.0.0.0 0 0 RDOF -
4. Configure route filtering:
# Reference IP prefix lists on Switch B to filter received and redistributed routes.
[SwitchB] ip prefix-list aaa index 10 permit 2.1.1.0 24
[SwitchB] ip prefix-list bbb index 10 permit 10.1.1.0 24
[SwitchB] ip prefix-list bbb index 11 permit 0.0.0.0 0 less-equal 32
[SwitchB] rip 1
[SwitchB-rip-1] filter-policy prefix-list aaa import
[SwitchB-rip-1] filter-policy prefix-list bbb export
[SwitchB-rip-1] quit
# Display the RIP routing table on Switch A.
[SwitchA] display rip 100 route
Route Flags: R - RIP, T - TRIP
P - Permanent, A - Aging, S - Suppressed, G - Garbage-collect
----------------------------------------------------------------------------
Peer 1.1.1.2 on Vlan-interface100
Destination/Mask Nexthop Cost Tag Flags Sec
10.1.1.0/24 1.1.1.2 1 0 RAOF 19
Local route
Destination/Mask Nexthop Cost Tag Flags Sec
1.1.1.0/24 0.0.0.0 0 0 RDOF -
2.1.1.0/24 0.0.0.0 0 0 RDOF -
3.1.1.0/24 0.0.0.0 0 0 RDOF -
# Display the RIP routing table on Switch B.
[SwitchB] display rip 1 route
Route Flags: R - RIP, T - TRIP
P - Permanent, A - Aging, S - Suppressed, G - Garbage-collect
D - Direct, O - Optimal, F - Flush to RIB
----------------------------------------------------------------------------
Peer 1.1.1.1 on Vlan-interface100
Destination/Mask Nexthop Cost Tag Flags Sec
2.1.1.0/24 1.1.1.3 1 0 RAOF 19
Local route
Destination/Mask Nexthop Cost Tag Flags Sec
1.1.1.0/24 0.0.0.0 0 0 RDOF -
10.1.1.0/24 0.0.0.0 0 0 RDOF -
10.2.1.0/24 0.0.0.0 0 0 RDOF -
Configuring RIP route redistribution
Network requirements
As shown in Figure 8, Switch B communicates with Switch A through RIP 100 and with Switch C through RIP 200.
Configure RIP 200 to redistribute direct routes and routes from RIP 100 on Switch B so Switch C can learn routes destined for 10.2.1.0/24 and 11.1.1.0/24. Switch A cannot learn routes destined for 12.3.1.0/24 and 16.4.1.0/24.
Configuration procedure
1. Configure IP addresses for interfaces. (Details not shown.)
2. Configure basic RIP:
# Enable RIP 100, and configure RIPv2 on Switch A.
<SwitchA> system-view
[SwitchA] rip 100
[SwitchA-rip-100] network 10.0.0.0
[SwitchA-rip-100] network 11.0.0.0
[SwitchA-rip-100] version 2
[SwitchA-rip-100] undo summary
[SwitchA-rip-100] quit
# Enable RIP 100 and RIP 200, and configure RIPv2 on Switch B.
<SwitchB> system-view
[SwitchB] rip 100
[SwitchB-rip-100] network 11.0.0.0
[SwitchB-rip-100] version 2
[SwitchB-rip-100] undo summary
[SwitchB-rip-100] quit
[SwitchB] rip 200
[SwitchB-rip-200] network 12.0.0.0
[SwitchB-rip-200] version 2
[SwitchB-rip-200] undo summary
[SwitchB-rip-200] quit
# Enable RIP 200, and configure RIPv2 on Switch C.
<SwitchC> system-view
[SwitchC] rip 200
[SwitchC-rip-200] network 12.0.0.0
[SwitchC-rip-200] network 16.0.0.0
[SwitchC-rip-200] version 2
[SwitchC-rip-200] undo summary
[SwitchC-rip-200] quit
# Display the IP routing table on Switch C.
[SwitchC] display ip routing-table
Destinations : 13 Routes : 13
Destination/Mask Proto Pre Cost NextHop Interface
0.0.0.0/32 Direct 0 0 127.0.0.1 InLoop0
12.3.1.0/24 Direct 0 0 12.3.1.2 Vlan200
12.3.1.0/32 Direct 0 0 12.3.1.2 Vlan200
12.3.1.2/32 Direct 0 0 127.0.0.1 InLoop0
12.3.1.255/32 Direct 0 0 12.3.1.2 Vlan200
16.4.1.0/24 Direct 0 0 16.4.1.1 Vlan400
16.4.1.0/32 Direct 0 0 16.4.1.1 Vlan400
16.4.1.1/32 Direct 0 0 127.0.0.1 InLoop0
16.4.1.255/32 Direct 0 0 16.4.1.1 Vlan400
127.0.0.0/8 Direct 0 0 127.0.0.1 InLoop0
127.0.0.0/32 Direct 0 0 127.0.0.1 InLoop0
127.0.0.1/32 Direct 0 0 127.0.0.1 InLoop0
127.255.255.255/32 Direct 0 0 127.0.0.1 InLoop0
3. Configure route redistribution:
# Configure RIP 200 to redistribute routes from RIP 100 and direct routes on Switch B.
[SwitchB] rip 200
[SwitchB-rip-200] import-route rip 100
[SwitchB-rip-200] import-route direct
[SwitchB-rip-200] quit
# Display the IP routing table on Switch C.
[SwitchC] display ip routing-table
Destinations : 15 Routes : 15
Destination/Mask Proto Pre Cost NextHop Interface
0.0.0.0/32 Direct 0 0 127.0.0.1 InLoop0
10.2.1.0/24 RIP 100 1 12.3.1.1 Vlan200
11.1.1.0/24 RIP 100 1 12.3.1.1 Vlan200
12.3.1.0/24 Direct 0 0 12.3.1.2 Vlan200
12.3.1.0/32 Direct 0 0 12.3.1.2 Vlan200
12.3.1.2/32 Direct 0 0 127.0.0.1 InLoop0
12.3.1.255/32 Direct 0 0 12.3.1.2 Vlan200
16.4.1.0/24 Direct 0 0 16.4.1.1 Vlan400
16.4.1.0/32 Direct 0 0 16.4.1.1 Vlan400
16.4.1.1/32 Direct 0 0 127.0.0.1 InLoop0
16.4.1.255/32 Direct 0 0 16.4.1.1 Vlan400
127.0.0.0/8 Direct 0 0 127.0.0.1 InLoop0
127.0.0.0/32 Direct 0 0 127.0.0.1 InLoop0
127.0.0.1/32 Direct 0 0 127.0.0.1 InLoop0
127.255.255.255/32 Direct 0 0 127.0.0.1 InLoop0
Configuring an additional metric for a RIP interface
Network requirements
As shown in Figure 9, run RIPv2 on all the interfaces of Switch A, Switch B, Switch C, Switch D, and Switch E.
Switch A has two links to Switch D. The link from Switch B to Switch D is more stable than that from Switch C to Switch D. Configure an additional metric for RIP routes received from VLAN-interface 200 on Switch A so Switch A prefers route 1.1.5.0/24 learned from Switch B.
Configuration procedure
1. Configure IP addresses for interfaces. (Details not shown.)
2. Configure basic RIP:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] rip 1
[SwitchA-rip-1] network 1.0.0.0
[SwitchA-rip-1] version 2
[SwitchA-rip-1] undo summary
[SwitchA-rip-1] quit
# Configure Switch B.
<SwitchB> system-view
[SwitchB] rip 1
[SwitchB-rip-1] network 1.0.0.0
[SwitchB-rip-1] version 2
[SwitchB-rip-1] undo summary
# Configure Switch C.
<SwitchC> system-view
[SwitchB] rip 1
[SwitchC-rip-1] network 1.0.0.0
[SwitchC-rip-1] version 2
[SwitchC-rip-1] undo summary
# Configure Switch D.
<SwitchD> system-view
[SwitchD] rip 1
[SwitchD-rip-1] network 1.0.0.0
[SwitchD-rip-1] version 2
[SwitchD-rip-1] undo summary
# Configure Switch E.
<SwitchE> system-view
[SwitchE] rip 1
[SwitchE-rip-1] network 1.0.0.0
[SwitchE-rip-1] version 2
[SwitchE-rip-1] undo summary
# Display all active routes in the RIP database on Switch A.
[SwitchA] display rip 1 database
1.0.0.0/8, auto-summary
1.1.1.0/24, cost 0, nexthop 1.1.1.1, RIP-interface
1.1.2.0/24, cost 0, nexthop 1.1.2.1, RIP-interface
1.1.3.0/24, cost 1, nexthop 1.1.1.2
1.1.4.0/24, cost 1, nexthop 1.1.2.2
1.1.5.0/24, cost 2, nexthop 1.1.1.2
1.1.5.0/24, cost 2, nexthop 1.1.2.2
The output shows two RIP routes destined for network 1.1.5.0/24, with the next hops as Switch B (1.1.1.2) and Switch C (1.1.2.2), and with the same cost of 2.
3. Configure an additional metric for a RIP interface:
# Configure an inbound additional metric of 3 for RIP-enabled interface VLAN-interface 200 on Switch A.
[SwitchA] interface vlan-interface 200
[SwitchA-Vlan-interface200] rip metricin 3
# Display all active routes in the RIP database on Switch A.
[SwitchA-Vlan-interface200] display rip 1 database
1.0.0.0/8, auto-summary
1.1.1.0/24, cost 0, nexthop 1.1.1.1, RIP-interface
1.1.2.0/24, cost 0, nexthop 1.1.2.1, RIP-interface
1.1.3.0/24, cost 1, nexthop 1.1.1.2
1.1.4.0/24, cost 2, nexthop 1.1.1.2
1.1.5.0/24, cost 2, nexthop 1.1.1.2
The output shows that only one RIP route reaches network 1.1.5.0/24, with the next hop as Switch B (1.1.1.2) and a cost of 2.
Configuring RIP to advertise a summary route
Network requirements
As shown in Figure 10, Switch A and Switch B run OSPF, Switch D runs RIP, and Switch C runs OSPF and RIP. Configure RIP to redistribute OSPF routes on Switch C so Switch D can learn routes destined for networks 10.1.1.0/24, 10.2.1.0/24, 10.5.1.0/24, and 10.6.1.0/24.
To reduce the routing table size of Switch D, configure route summarization on Switch C to advertise only the summary route 10.0.0.0/8 to Switch D.
Configuration procedure
1. Configure IP addresses for interfaces. (Details not shown.)
2. Configure basic OSPF:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] ospf
[SwitchA-ospf-1] area 0
[SwitchA-ospf-1-area-0.0.0.0] network 10.5.1.0 0.0.0.255
[SwitchA-ospf-1-area-0.0.0.0] network 10.2.1.0 0.0.0.255
[SwitchA-ospf-1-area-0.0.0.0] quit
# Configure Switch B.
<SwitchB> system-view
[SwitchB] ospf
[SwitchB-ospf-1] area 0
[SwitchB-ospf-1-area-0.0.0.0] network 10.1.1.0 0.0.0.255
[SwitchB-ospf-1-area-0.0.0.0] network 10.6.1.0 0.0.0.255
[SwitchB-ospf-1-area-0.0.0.0] quit
# Configure Switch C.
<SwitchC> system-view
[SwitchC] ospf
[SwitchC-ospf-1] area 0
[SwitchC-ospf-1-area-0.0.0.0] network 10.1.1.0 0.0.0.255
[SwitchC-ospf-1-area-0.0.0.0] network 10.2.1.0 0.0.0.255
[SwitchC-ospf-1-area-0.0.0.0] quit
[SwitchC-ospf-1] quit
3. Configure basic RIP:
# Configure Switch C.
[SwitchC] rip 1
[SwitchC-rip-1] network 11.3.1.0
[SwitchC-rip-1] version 2
[SwitchC-rip-1] undo summary
# Configure Switch D.
<SwitchD> system-view
[SwitchD] rip 1
[SwitchD-rip-1] network 11.0.0.0
[SwitchD-rip-1] version 2
[SwitchD-rip-1] undo summary
[SwitchD-rip-1] quit
# Configure RIP to redistribute routes from OSPF process 1 and direct routes on Switch C.
[SwitchC-rip-1] import-route direct
[SwitchC-rip-1] import-route ospf 1
[SwitchC-rip-1] quit
# Display the IP routing table on Switch D.
[SwitchD] display ip routing-table
Destinations : 15 Routes : 15
Destination/Mask Proto Pre Cost NextHop Interface
0.0.0.0/32 Direct 0 0 127.0.0.1 InLoop0
10.1.1.0/24 RIP 100 1 11.3.1.1 Vlan300
10.2.1.0/24 RIP 100 1 11.3.1.1 Vlan300
10.5.1.0/24 RIP 100 1 11.3.1.1 Vlan300
10.6.1.0/24 RIP 100 1 11.3.1.1 Vlan300
11.3.1.0/24 Direct 0 0 11.3.1.2 Vlan300
11.3.1.0/32 Direct 0 0 11.3.1.2 Vlan300
11.3.1.2/32 Direct 0 0 127.0.0.1 InLoop0
11.4.1.0/24 Direct 0 0 11.4.1.2 Vlan400
11.4.1.0/32 Direct 0 0 11.4.1.2 Vlan400
11.4.1.2/32 Direct 0 0 127.0.0.1 InLoop0
127.0.0.0/8 Direct 0 0 127.0.0.1 InLoop0
127.0.0.0/32 Direct 0 0 127.0.0.1 InLoop0
127.0.0.1/32 Direct 0 0 127.0.0.1 InLoop0
127.255.255.255/32 Direct 0 0 127.0.0.1 InLoop0
4. Configure route summarization:
# Configure route summarization on Switch C and advertise only the summary route 10.0.0.0/8.
[SwitchC] interface vlan-interface 300
[SwitchC-Vlan-interface300] rip summary-address 10.0.0.0 8
# Display the IP routing table on Switch D.
[SwitchD] display ip routing-table
Destinations : 12 Routes : 12
Destination/Mask Proto Pre Cost NextHop Interface
0.0.0.0/32 Direct 0 0 127.0.0.1 InLoop0
10.0.0.0/8 RIP 100 1 11.3.1.1 Vlan300
11.3.1.0/24 Direct 0 0 11.3.1.2 Vlan300
11.3.1.0/32 Direct 0 0 11.3.1.2 Vlan300
11.3.1.2/32 Direct 0 0 127.0.0.1 InLoop0
11.4.1.0/24 Direct 0 0 11.4.1.2 Vlan400
11.4.1.0/32 Direct 0 0 11.4.1.2 Vlan400
11.4.1.2/32 Direct 0 0 127.0.0.1 InLoop0
127.0.0.0/8 Direct 0 0 127.0.0.1 InLoop0
127.0.0.0/32 Direct 0 0 127.0.0.1 InLoop0
127.0.0.1/32 Direct 0 0 127.0.0.1 InLoop0
127.255.255.255/32 Direct 0 0 127.0.0.1 InLoop0
Configuring RIP GR
Network requirements
As shown in Figure 11, Switch A, Switch B, and Switch C all run RIPv2.
· Enable GR on Switch A. Switch A acts as the GR restarter.
· Switch B and Switch C act as GR helpers to synchronize their routing tables with Switch A by using GR.
Configuration procedure
1. Configure IP addresses and subnet masks for interfaces on the switches. (Details not shown.)
2. Configure RIPv2 on the switches to ensure the following: (Details not shown.)
? Switch A, Switch B, and Switch C can communicate with each other at Layer 3.
? Dynamic route update can be implemented among them with RIPv2.
3. Enable RIP GR on Switch A.
<SwitchA> system-view
[SwitchA] rip
[SwitchA-rip-1] graceful-restart
Verifying the configuration
# Restart RIP process 1 on Switch A.
[SwitchA-rip-1] return
<SwitchA> reset rip 1 process
Reset RIP process? [Y/N]:y
# Display GR status on Switch A.
<SwitchA> display rip graceful-restart
RIP process: 1
Graceful Restart capability : Enabled
Current GR state : Normal
Graceful Restart period : 60 seconds
Graceful Restart remaining time : 0 seconds
Configuring RIP NSR
Network requirements
As shown in Figure 12, Switch A, Switch B, and Switch S all run RIPv2.
Enable RIP NSR on Switch S to ensure correct routing when an active/standby switchover occurs on Switch S.
Configuration procedure
1. Configure IP addresses and subnet masks for interfaces on the switches. (Details not shown.)
2. Configure RIPv2 on the switches to ensure the following: (Details not shown.)
? Switch A, Switch B, and Switch S can communicate with each other at Layer 3.
? Dynamic route update can be implemented among them with RIPv2.
3. Enable RIP NSR on Switch S.
<SwitchS> system-view
[SwitchS] rip 100
[SwitchS-rip-100] non-stop-routing
[SwitchS-rip-100] quit
Verifying the configuration
# Perform an active/standby switchover on Switch S.
[SwitchS] placement reoptimize
Predicted changes to the placement
Program Current location New location
---------------------------------------------------------------------
lb 0/0 0/0
lsm 0/0 0/0
slsp 0/0 0/0
rib6 0/0 0/0
routepolicy 0/0 0/0
rib 0/0 0/0
staticroute6 0/0 0/0
staticroute 0/0 0/0
ospf 0/0 1/0
Continue? [y/n]:y
Re-optimization of the placement start. You will be notified on completion
Re-optimization of the placement complete. Use 'display placement' to view the new placement
# Display neighbor information and route information on Switch A.
[SwitchA] display rip 1 neighbor
Neighbor Address: 12.12.12.2
Interface : Vlan-interface200
Version : RIPv2 Last update: 00h00m13s
Relay nbr : No BFD session: None
Bad packets: 0 Bad routes : 0
[SwitchA] display rip 1 route
Route Flags: R - RIP, T - TRIP
P - Permanent, A - Aging, S - Suppressed, G - Garbage-collect
D - Direct, O - Optimal, F - Flush to RIB
----------------------------------------------------------------------------
Peer 12.12.12.2 on Vlan-interface200
Destination/Mask Nexthop Cost Tag Flags Sec
14.0.0.0/8 12.12.12.2 1 0 RAOF 16
44.0.0.0/8 12.12.12.2 2 0 RAOF 16
Local route
Destination/Mask Nexthop Cost Tag Flags Sec
12.12.12.0/24 0.0.0.0 0 0 RDOF -
22.22.22.22/32 0.0.0.0 0 0 RDOF -
# Display neighbor information and route information on Switch B.
[SwitchB] display rip 1 neighbor
Neighbor Address: 14.14.14.2
Interface : Vlan-interface200
Version : RIPv2 Last update: 00h00m32s
Relay nbr : No BFD session: None
Bad packets: 0 Bad routes : 0
[SwitchB] display rip 1 route
Route Flags: R - RIP, T - TRIP
P - Permanent, A - Aging, S - Suppressed, G - Garbage-collect
D - Direct, O - Optimal, F - Flush to RIB
----------------------------------------------------------------------------
Peer 14.14.14.2 on Vlan-interface200
Destination/Mask Nexthop Cost Tag Flags Sec
12.0.0.0/8 14.14.14.2 1 0 RAOF 1
22.0.0.0/8 14.14.14.2 2 0 RAOF 1
Local route
Destination/Mask Nexthop Cost Tag Flags Sec
44.44.44.44/32 0.0.0.0 0 0 RDOF -
14.14.14.0/24 0.0.0.0 0 0 RDOF -
The output shows that the neighbor and route information on Switch A and Switch B keep unchanged during the active/standby switchover on Switch S. The traffic from Switch A to Switch B has not been impacted.
Configuring BFD for RIP (single-hop echo detection for a directly connected neighbor)
Network requirements
As shown in Figure 13, VLAN-interface 100 of Switch A and Switch C runs RIP process 1. VLAN-interface 200 of Switch A runs RIP process 2. VLAN-interface 300 of Switch C and VLAN-interface 200 and VLAN-interface 300 of Switch B run RIP process 1.
· Configure a static route destined for 100.1.1.1/24 and enable static route redistribution into RIP on Switch C. This allows Switch A to learn two routes destined for 100.1.1.1/24 through VLAN-interface 100 and VLAN-interface 200 respectively, and uses the one through VLAN-interface 100.
· Enable BFD for RIP on VLAN-interface 100 of Switch A. When the link over VLAN-interface 100 fails, BFD can quickly detect the failure and notify RIP. RIP deletes the neighbor relationship and route information learned on VLAN-interface 100, and uses the route destined for 100.1.1.1 24 through VLAN-interface 200.
Configuration procedure
1. Configure IP addresses for interfaces. (Details not shown.)
2. Configure basic RIP:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] rip 1
[SwitchA-rip-1] version 2
[SwitchA-rip-1] undo summary
[SwitchA-rip-1] network 192.168.1.0
[SwitchA-rip-1] quit
[SwitchA] interface vlan-interface 100
[SwitchA-Vlan-interface100] rip bfd enable
[SwitchA-Vlan-interface100] quit
[SwitchA] rip 2
[SwitchA-rip-2] version 2
[SwitchA-rip-2] undo summary
[SwitchA-rip-2] network 192.168.2.0
[SwitchA-rip-2] quit
# Configure Switch B.
<SwitchB> system-view
[SwitchB] rip 1
[SwitchB-rip-1] version 2
[SwitchB-rip-1] undo summary
[SwitchB-rip-1] network 192.168.2.0
[SwitchB-rip-1] network 192.168.3.0
[SwitchB-rip-1] quit
# Configure Switch C.
<SwitchC> system-view
[SwitchC] rip 1
[SwitchC-rip-1] version 2
[SwitchC-rip-1] undo summary
[SwitchC-rip-1] network 192.168.1.0
[SwitchC-rip-1] network 192.168.3.0
[SwitchC-rip-1] import-route static
[SwitchC-rip-1] quit
3. Configure BFD parameters on VLAN-interface 100 of Switch A.
[SwitchA] bfd echo-source-ip 11.11.11.11
[SwitchA] interface vlan-interface 100
[SwitchA-Vlan-interface100] bfd min-transmit-interval 500
[SwitchA-Vlan-interface100] bfd min-receive-interval 500
[SwitchA-Vlan-interface100] bfd detect-multiplier 7
[SwitchA-Vlan-interface100] quit
[SwitchA] quit
4. Configure a static route on Switch C.
[SwitchC] ip route-static 120.1.1.1 24 null 0
Verifying the configuration
# Display the BFD session information on Switch A.
<SwitchA> display bfd session
Total Session Num: 1 Up Session Num: 1 Init Mode: Active
IPv4 Session Working Under Echo Mode:
LD SourceAddr DestAddr State Holdtime Interface
4 192.168.1.1 192.168.1.2 Up 2000ms Vlan100
# Display RIP routes destined for 120.1.1.0/24 on Switch A.
<SwitchA> display ip routing-table 120.1.1.0 24
Summary count : 1
Destination/Mask Proto Pre Cost NextHop Interface
120.1.1.0/24 RIP 100 1 192.168.1.2 Vlan-interface100
The output shows that Switch A communicates with Switch C through VLAN-interface 100. Then the link over VLAN-interface 100 fails.
# Display RIP routes destined for 120.1.1.0/24 on Switch A.
<SwitchA> display ip routing-table 120.1.1.0 24
Summary count : 1
Destination/Mask Proto Pre Cost NextHop Interface
120.1.1.0/24 RIP 100 1 192.168.2.2 Vlan-interface200
The output shows that Switch A communicates with Switch C through VLAN-interface 200.
Configuring BFD for RIP (single hop echo detection for a specific destination)
Network requirements
As shown in Figure 14, VLAN-interface 100 of Switch A and Switch B runs RIP process 1. VLAN-interface 200 of Switch B and Switch C runs RIP process 1.
· Configure a static route destined for 100.1.1.0/24 and enable static route redistribution into RIP on both Switch A and Switch C. This allows Switch B to learn two routes destined for 100.1.1.0/24 through VLAN-interface 100 and VLAN-interface 200. The route redistributed from Switch A has a smaller cost than that redistributed from Switch C, so Switch B uses the route through VLAN-interface 200.
· Enable BFD for RIP on VLAN-interface 100 of Switch A, and specify VLAN-interface 100 of Switch B as the destination. When a unidirectional link occurs between Switch A and Switch B, BFD can quickly detect the link failure and notify RIP. Switch B then deletes the neighbor relationship and the route information learned on VLAN-interface 100. It does not receive or send any packets from VLAN-interface 100. When the route learned from Switch A ages out, Switch B uses the route destined for 100.1.1.1 24 through VLAN-interface 200.
Configuration procedure
1. Configure IP addresses for interfaces. (Details not shown.)
2. Configure basic RIP and enable BFD on the interfaces:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] rip 1
[SwitchA-rip-1] network 192.168.2.0
[SwitchA-rip-1] import-route static
[SwitchA-rip-1] quit
[SwitchA] interface vlan-interface 100
[SwitchA-Vlan-interface100] rip bfd enable destination 192.168.2.2
[SwitchA-Vlan-interface100] quit
# Configure Switch B.
<SwitchB> system-view
[SwitchB] rip 1
[SwitchB-rip-1] network 192.168.2.0
[SwitchB-rip-1] network 192.168.3.0
[SwitchB-rip-1] quit
# Configure Switch C.
<SwitchC> system-view
[SwitchC] rip 1
[SwitchC-rip-1] network 192.168.3.0
[SwitchC-rip-1] import-route static cost 3
[SwitchC-rip-1] quit
3. Configure BFD parameters on VLAN-interface 100 of Switch A.
[SwitchA] bfd echo-source-ip 11.11.11.11
[SwitchA] interface vlan-interface 100
[SwitchA-Vlan-interface100] bfd min-echo-receive-interval 500
[SwitchA-Vlan-interface100] return
4. Configure static routes:
# Configure a static route on Switch A.
[SwitchA] ip route-static 100.1.1.0 24 null 0
# Configure a static route on Switch C.
[SwitchA] ip route-static 100.1.1.0 24 null 0
Verifying the configuration
# Display BFD session information on Switch A.
<SwitchA> display bfd session
Total Session Num: 1 Up Session Num: 1 Init Mode: Active
IPv4 session working under Echo mode:
LD SourceAddr DestAddr State Holdtime Interface
3 192.168.2.1 192.168.2.2 Up 2000ms vlan100
# Display routes destined for 100.1.1.0/24 on Switch B.
<SwitchB> display ip routing-table 100.1.1.0 24 verbose
Summary Count : 1
Destination: 100.1.1.0/24
Protocol: RIP
Process ID: 1
SubProtID: 0x1 Age: 00h02m47s
Cost: 1 Preference: 100
IpPre: N/A QosLocalID: N/A
Tag: 0 State: Active Adv
OrigTblID: 0x0 OrigVrf: default-vrf
TableID: 0x2 OrigAs: 0
NibID: 0x12000002 LastAs: 0
AttrID: 0xffffffff Neighbor: 192.168.2.1
Flags: 0x1008c OrigNextHop: 192.168.2.1
Label: NULL RealNextHop: 192.168.2.1
BkLabel: NULL BkNextHop: N/A
Tunnel ID: Invalid Interface: vlan-interface 100
BkTunnel ID: Invalid BkInterface: N/A
FtnIndex: 0x0 TrafficIndex: N/A
Connector: N/A
# Display routes destined for 100.1.1.0/24 on Switch B when the link between Switch A and Switch B fails.
<SwitchB> display ip routing-table 100.1.1.0 24 verbose
Summary Count : 1
Destination: 100.1.1.0/24
Protocol: RIP
Process ID: 1
SubProtID: 0x1 Age: 00h21m23s
Cost: 4 Preference: 100
IpPre: N/A QosLocalID: N/A
Tag: 0 State: Active Adv
OrigTblID: 0x0 OrigVrf: default-vrf
TableID: 0x2 OrigAs: 0
NibID: 0x12000002 LastAs: 0
AttrID: 0xffffffff Neighbor: 192.168.3.2
Flags: 0x1008c OrigNextHop: 192.168.3.2
Label: NULL RealNextHop: 192.168.3.2
BkLabel: NULL BkNextHop: N/A
Tunnel ID: Invalid Interface: vlan-interface 200
BkTunnel ID: Invalid BkInterface: N/A
FtnIndex: 0x0 TrafficIndex: N/A
Connector: N/A
Configuring BFD for RIP (bidirectional detection in BFD control packet mode)
Network requirements
As shown in Figure 15, VLAN-interface 100 of Switch A and VLAN-interface 200 of Switch C run RIP process 1.
VLAN-interface 300 of Switch A runs RIP process 2. VLAN-interface 400 of Switch C, and VLAN-interface 300 and VLAN-interface 400 of Switch D run RIP process 1.
· Configure a static route destined for 100.1.1.0/24 on Switch A.
· Configure a static route destined for 101.1.1.0/24 on Switch C.
· Enable static route redistribution into RIP on Switch A and Switch C. This allows Switch A to learn two routes destined for 100.1.1.0/24 through VLAN-interface 100 and VLAN-interface 300. It uses the route through VLAN-interface 100.
· Enable BFD on VLAN-interface 100 of Switch A and VLAN-interface 200 of Switch C.
When the link over VLAN-interface 100 fails, BFD can quickly detect the link failure and notify RIP. RIP deletes the neighbor relationship and the route information received learned on VLAN-interface 100. It uses the route destined for 100.1.1.0/24 through VLAN-interface 300.
Table 7 Interface and IP address assignment
Device |
Interface |
IP address |
Switch A |
VLAN-interface 300 |
192.168.3.1/24 |
Switch A |
VLAN-interface 100 |
192.168.1.1/24 |
Switch B |
VLAN-interface 100 |
192.168.1.2/24 |
Switch B |
VLAN-interface 200 |
192.168.2.1/24 |
Switch C |
VLAN-interface 200 |
192.168.2.2/24 |
Switch C |
VLAN-interface 400 |
192.168.4.2/24 |
Switch D |
VLAN-interface 300 |
192.168.3.2/24 |
Switch D |
VLAN-interface 400 |
192.168.4.1/24 |
Configuration procedure
1. Configure IP addresses for interfaces. (Details not shown.)
2. Configure basic RIP and enable static route redistribution into RIP so Switch A and Switch C have routes to send to each other:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] rip 1
[SwitchA-rip-1] version 2
[SwitchA-rip-1] undo summary
[SwitchA-rip-1] network 192.168.1.0
[SwitchA-rip-1] network 101.1.1.0
[SwitchA-rip-1] peer 192.168.2.2
[SwitchA-rip-1] undo validate-source-address
[SwitchA-rip-1] import-route static
[SwitchA-rip-1] quit
[SwitchA] interface vlan-interface 100
[SwitchA-Vlan-interface100] rip bfd enable
[SwitchA-Vlan-interface100] quit
[SwitchA] rip 2
[SwitchA-rip-2] version 2
[SwitchA-rip-2] undo summary
[SwitchA-rip-2] network 192.168.3.0
[SwitchA-rip-2] quit
# Configure Switch C.
<SwitchC> system-view
[SwitchC] rip 1
[SwitchC-rip-1] version 2
[SwitchC-rip-1] undo summary
[SwitchC-rip-1] network 192.168.2.0
[SwitchC-rip-1] network 192.168.4.0
[SwitchC-rip-1] network 100.1.1.0
[SwitchC-rip-1] peer 192.168.1.1
[SwitchC-rip-1] undo validate-source-address
[SwitchC-rip-1] import-route static
[SwitchC-rip-1] quit
[SwitchC] interface vlan-interface 200
[SwitchC-Vlan-interface200] rip bfd enable
[SwitchC-Vlan-interface200] quit
# Configure Switch D.
<SwitchD> system-view
[SwitchD] rip 1
[SwitchD-rip-1] version 2
[SwitchD-rip-1] undo summary
[SwitchD-rip-1] network 192.168.3.0
[SwitchD-rip-1] network 192.168.4.0
3. Configure BFD parameters:
# Configure Switch A.
[SwitchA] bfd session init-mode active
[SwitchA] interface vlan-interface 100
[SwitchA-Vlan-interface100] bfd min-transmit-interval 500
[SwitchA-Vlan-interface100] bfd min-receive-interval 500
[SwitchA-Vlan-interface100] bfd detect-multiplier 7
[SwitchA-Vlan-interface100] quit
# Configure Switch C.
[SwitchC] bfd session init-mode active
[SwitchC] interface vlan-interface 200
[SwitchC-Vlan-interface200] bfd min-transmit-interval 500
[SwitchC-Vlan-interface200] bfd min-receive-interval 500
[SwitchC-Vlan-interface200] bfd detect-multiplier 7
[SwitchC-Vlan-interface200] quit
4. Configure static routes:
# Configure a static route to Switch C on Switch A.
[SwitchA] ip route-static 192.168.2.0 24 vlan-interface 100 192.168.1.2
[SwitchA] quit
# Configure a static route to Switch A on Switch C.
[SwitchC] ip route-static 192.168.1.0 24 vlan-interface 200 192.168.2.1
Verifying the configuration
# Display the BFD session information on Switch A.
<SwitchA> display bfd session
Total Session Num: 1 Up Session Num: 1 Init Mode: Active
IPv4 session working under Ctrl mode:
LD/RD SourceAddr DestAddr State Holdtime Interface
513/513 192.168.1.1 192.168.2.2 Up 1700ms vlan100
# Display RIP routes destined for 100.1.1.0/24 on Switch A.
<SwitchA> display ip routing-table 100.1.1.0 24
Summary count : 1
Destination/Mask Proto Pre Cost NextHop Interface
100.1.1.0/24 RIP 100 1 192.168.2.2 vlan-interface 100
The output shows that Switch A communicates with Switch C through VLAN-interface 100. Then the link over VLAN-interface 100 fails.
# Display RIP routes destined for 100.1.1.0/24 on Switch A.
<SwitchA> display ip routing-table 100.1.1.0 24
Summary count : 1
Destination/Mask Proto Pre Cost NextHop Interface
100.1.1.0/24 RIP 100 2 192.168.3.2 vlan-interface 300
The output shows that Switch A communicates with Switch C through VLAN-interface 300.
Configuring RIP FRR
Network requirements
As shown in Figure 16, Switch A, Switch B, and Switch C run RIPv2. Configure RIP FRR so that when Link A becomes unidirectional, services can be switched to Link B immediately.
Table 8 Interface and IP address assignment
Device |
Interface |
IP address |
Switch A |
VLAN-interface 100 |
12.12.12.1/24 |
Switch A |
VLAN-interface 200 |
13.13.13.1/24 |
Switch A |
Loopback 0 |
1.1.1.1/32 |
Switch B |
VLAN-interface 101 |
24.24.24.4/24 |
Switch B |
VLAN-interface 200 |
13.13.13.2/24 |
Switch B |
Loopback 0 |
4.4.4.4/32 |
Switch C |
VLAN-interface 100 |
12.12.12.2/24 |
Switch C |
VLAN-interface 101 |
24.24.24.2/24 |
Configuration procedure
1. Configure IP addresses and subnet masks for interfaces on the switches. (Details not shown.)
2. Configure RIPv2 on the switches to make sure Switch A, Switch B, and Switch C can communicate with each other at Layer 3. (Details not shown.)
3. Configure RIP FRR:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] ip prefix-list abc index 10 permit 4.4.4.4 32
[SwitchA] route-policy frr permit node 10
[SwitchA-route-policy-frr-10] if-match ip address prefix-list abc
[SwitchA-route-policy-frr-10] apply fast-reroute backup-interface vlan-interface 100 backup-nexthop 12.12.12.2
[SwitchA-route-policy-frr-10] quit
[SwitchA] rip 1
[SwitchA-rip-1] fast-reroute route-policy frr
[SwitchA-rip-1] quit
# Configure Switch B.
<SwitchB> system-view
[SwitchB] ip prefix-list abc index 10 permit 1.1.1.1 32
[SwitchB] route-policy frr permit node 10
[SwitchB-route-policy-frr-10] if-match ip address prefix-list abc
[SwitchB-route-policy-frr-10] apply fast-reroute backup-interface vlan-interface 101 backup-nexthop 24.24.24.2
[SwitchB-route-policy-frr-10] quit
[SwitchB] rip 1
[SwitchB-rip-1] fast-reroute route-policy frr
[SwitchB-rip-1] quit
Verifying the configuration
# Display route 4.4.4.4/32 on Switch A to view the backup next hop information.
[SwitchA] display ip routing-table 4.4.4.4 verbose
Summary Count : 1
Destination: 4.4.4.4/32
Protocol: RIP
Process ID: 1
SubProtID: 0x1 Age: 04h20m37s
Cost: 1 Preference: 100
IpPre: N/A QosLocalID: N/A
Tag: 0 State: Active Adv
OrigTblID: 0x0 OrigVrf: default-vrf
TableID: 0x2 OrigAs: 0
NibID: 0x26000002 LastAs: 0
AttrID: 0xffffffff Neighbor: 13.13.13.2
Flags: 0x1008c OrigNextHop: 13.13.13.2
Label: NULL RealNextHop: 13.13.13.2
BkLabel: NULL BkNextHop: 12.12.12.2
Tunnel ID: Invalid Interface: Vlan-interface200
BkTunnel ID: Invalid BkInterface: Vlan-interface100
FtnIndex: 0x0 TrafficIndex: N/A
Connector: N/A
# Display route 1.1.1.1/32 on Switch B to view the backup next hop information.
[SwitchB] display ip routing-table 1.1.1.1 verbose
Summary Count : 1
Destination: 1.1.1.1/32
Protocol: RIP
Process ID: 1
SubProtID: 0x1 Age: 04h20m37s
Cost: 1 Preference: 100
IpPre: N/A QosLocalID: N/A
Tag: 0 State: Active Adv
OrigTblID: 0x0 OrigVrf: default-vrf
TableID: 0x2 OrigAs: 0
NibID: 0x26000002 LastAs: 0
AttrID: 0xffffffff Neighbor: 13.13.13.1
Flags: 0x1008c OrigNextHop: 13.13.13.1
Label: NULL RealNextHop: 13.13.13.1
BkLabel: NULL BkNextHop: 24.24.24.2
Tunnel ID: Invalid Interface: Vlan-interface200
BkTunnel ID: Invalid BkInterface: Vlan-interface101
FtnIndex: 0x0 TrafficIndex: N/A
Connector: N/A
Configuring OSPF
Overview
Open Shortest Path First (OSPF) is a link-state IGP developed by the OSPF working group of the IETF. OSPF version 2 is used for IPv4. OSPF refers to OSPFv2 throughout this chapter.
OSPF has the following features:
· Wide scope—Supports multiple network sizes and several hundred routers in an OSPF routing domain.
· Fast convergence—Advertises routing updates instantly upon network topology changes.
· Loop free—Computes routes with the SPF algorithm to avoid routing loops.
· Area-based network partition—Splits an AS into multiple areas to facilitate management. This feature reduces the LSDB size on routers to save memory and CPU resources, and reduces route updates transmitted between areas to save bandwidth.
· ECMP routing—Supports multiple equal-cost routes to a destination.
· Routing hierarchy—Supports a 4-level routing hierarchy that prioritizes routes into intra-area, inter-area, external Type-1, and external Type-2 routes.
· Authentication—Supports area- and interface-based packet authentication to ensure secure packet exchange.
· Support for multicasting—Multicasts protocol packets on some types of links to avoid impacting other devices.
OSPF packets
OSPF messages are carried directly over IP. The protocol number is 89.
OSPF uses the following packet types:
· Hello—Periodically sent to find and maintain neighbors, containing timer values, information about the DR, BDR, and known neighbors.
· Database description (DD)—Describes the digest of each LSA in the LSDB, exchanged between two routers for data synchronization.
· Link state request (LSR)—Requests needed LSAs from a neighbor. After exchanging the DD packets, the two routers know which LSAs of the neighbor are missing from their LSDBs. They then exchange LSR packets requesting the missing LSAs. LSR packets contain the digest of the missing LSAs.
· Link state update (LSU)—Transmits the requested LSAs to the neighbor.
· Link state acknowledgment (LSAck)—Acknowledges received LSU packets. It contains the headers of received LSAs (an LSAck packet can acknowledge multiple LSAs).
LSA types
OSPF advertises routing information in Link State Advertisements (LSAs). The following LSAs are commonly used:
· Router LSA—Type-1 LSA, originated by all routers and flooded throughout a single area only. This LSA describes the collected states of the router's interfaces to an area.
· Network LSA—Type-2 LSA, originated for broadcast and NBMA networks by the designated router, and flooded throughout a single area only. This LSA contains the list of routers connected to the network.
· Network Summary LSA—Type-3 LSA, originated by Area Border Routers (ABRs), and flooded throughout the LSA's associated area. Each summary-LSA describes a route to a destination outside the area, yet still inside the AS (an inter-area route).
· ASBR Summary LSA—Type-4 LSA, originated by ABRs and flooded throughout the LSA's associated area. Type 4 summary-LSAs describe routes to Autonomous System Boundary Router (ASBR).
· AS External LSA—Type-5 LSA, originated by ASBRs, and flooded throughout the AS (except stub and NSSA areas). Each AS-external-LSA describes a route to another AS.
· NSSA LSA—Type-7 LSA, as defined in RFC 1587, originated by ASBRs in NSSAs and flooded throughout a single NSSA. NSSA LSAs describe routes to other ASs.
· Opaque LSA—A proposed type of LSA. Its format consists of a standard LSA header and application specific information. Opaque LSAs are used by the OSPF protocol or by some applications to distribute information into the OSPF routing domain. The opaque LSA includes Type 9, Type 10, and Type 11. The Type 9 opaque LSA is flooded into the local subnet, the Type 10 is flooded into the local area, and the Type 11 is flooded throughout the AS.
OSPF areas
In large OSPF routing domains, SPF route computations consume too many storage and CPU resources, and enormous OSPF packets generated for route synchronization occupy excessive bandwidth.
To resolve these issues, OSPF splits an AS into multiple areas. Each area is identified by an area ID. The boundaries between areas are routers rather than links. A network segment (or a link) can only reside in one area as shown in Figure 17.
You can configure route summarization on ABRs to reduce the number of LSAs advertised to other areas and minimize the effect of topology changes.
Figure 17 Area-based OSPF network partition
Backbone area and virtual links
Each AS has a backbone area that distributes routing information between non-backbone areas. Routing information between non-backbone areas must be forwarded by the backbone area. OSPF has the following requirements:
· All non-backbone areas must maintain connectivity to the backbone area.
· The backbone area must maintain connectivity within itself.
In practice, these requirements might not be met due to lack of physical links. OSPF virtual links can solve this issue.
A virtual link is established between two ABRs through a non-backbone area. It must be configured on both ABRs to take effect. The non-backbone area is called a transit area.
As shown in Figure 18, Area 2 has no direct physical link to the backbone Area 0. You can configure a virtual link between the two ABRs to connect Area 2 to the backbone area.
Figure 18 Virtual link application 1
Virtual links can also be used as redundant links. If a physical link failure breaks the internal connectivity of the backbone area, you can configure a virtual link to replace the failed physical link, as shown in Figure 19.
Figure 19 Virtual link application 2
The virtual link between the two ABRs acts as a point-to-point connection. You can configure interface parameters, such as hello interval, on the virtual link as they are configured on a physical interface.
The two ABRs on the virtual link unicast OSPF packets to each other, and the OSPF routers in between convey these OSPF packets as normal IP packets.
Stub area and totally stub area
A stub area does not distribute Type-5 LSAs to reduce the routing table size and LSAs advertised within the area. The ABR of the stub area advertises a default route in a Type-3 LSA so that the routers in the area can reach external networks through the default route.
To further reduce the routing table size and advertised LSAs, you can configure the stub area as a totally stub area. The ABR of a totally stub area does not advertise inter-area routes or external routes. It advertises a default route in a Type-3 LSA so that the routers in the area can reach external networks through the default route.
NSSA area and totally NSSA area
An NSSA area does not import AS external LSAs (Type-5 LSAs) but can import Type-7 LSAs generated by the NSSA ASBR. The NSSA ABR translates Type-7 LSAs into Type-5 LSAs and advertises the Type-5 LSAs to other areas.
As shown in Figure 20, the OSPF AS contains Area 1, Area 2, and Area 0. The other two ASs run RIP. Area 1 is an NSSA area where the ASBR redistributes RIP routes in Type-7 LSAs into Area 1. Upon receiving the Type-7 LSAs, the NSSA ABR translates them to Type-5 LSAs, and advertises the Type-5 LSAs to Area 0.
The ASBR of Area 2 redistributes RIP routes in Type-5 LSAs into the OSPF routing domain. However, Area 1 does not receive Type-5 LSAs because it is an NSSA area.
Router types
OSPF routers are classified into the following types based on their positions in the AS:
· Internal router—All interfaces on an internal router belong to one OSPF area.
· ABR—Belongs to more than two areas, one of which must be the backbone area. ABR connects the backbone area to a non-backbone area. An ABR and the backbone area can be connected through a physical or logical link.
· Backbone router—No less than one interface of a backbone router must reside in the backbone area. All ABRs and internal routers in Area 0 are backbone routers.
· ASBR—Exchanges routing information with another AS is an ASBR. An ASBR might not reside on the border of the AS. It can be an internal router or an ABR.
Figure 21 OSPF router types
Route types
OSPF prioritizes routes into the following route levels:
· Intra-area route.
· Inter-area route.
· Type-1 external route.
· Type-2 external route.
The intra-area and inter-area routes describe the network topology of the AS. The external routes describe routes to external ASs.
A Type-1 external route has high credibility. The cost of a Type-1 external route = the cost from the router to the corresponding ASBR + the cost from the ASBR to the destination of the external route.
A Type-2 external route has low credibility. OSPF considers that the cost from the ASBR to the destination of a Type-2 external route is much greater than the cost from the ASBR to an OSPF internal router. The cost of a Type-2 external route = the cost from the ASBR to the destination of the Type-2 external route. If two Type-2 routes to the same destination have the same cost, OSPF takes the cost from the router to the ASBR into consideration to determine the best route.
Route calculation
OSPF computes routes in an area as follows:
· Each router generates LSAs based on the network topology around itself, and sends them to other routers in update packets.
· Each OSPF router collects LSAs from other routers to compose an LSDB. An LSA describes the network topology around a router, and the LSDB describes the entire network topology of the area.
· Each router transforms the LSDB to a weighted directed graph that shows the topology of the area. All the routers within the area have the same graph.
· Each router uses the SPF algorithm to compute a shortest path tree that shows the routes to the nodes in the area. The router itself is the root of the tree.
OSPF network types
OSPF classifies networks into the following types, depending on different link layer protocols:
· Broadcast—If the link layer protocol is Ethernet or FDDI, OSPF considers the network type as broadcast by default. On a broadcast network, hello, LSU, and LSAck packets are multicast to 224.0.0.5 that identifies all OSPF routers or to 224.0.0.6 that identifies the DR and BDR. DD packets and LSR packets are unicast.
· NBMA—If the link layer protocol is Frame Relay, ATM, or X.25, OSPF considers the network type as NBMA by default. OSPF packets are unicast on an NBMA network.
· P2MP—No link is P2MP type by default. P2MP must be a conversion from other network types such as NBMA. On a P2MP network, OSPF packets are multicast to 224.0.0.5.
· P2P—If the link layer protocol is PPP or HDLC, OSPF considers the network type as P2P. On a P2P network, OSPF packets are multicast to 224.0.0.5.
The following are the differences between NBMA and P2MP networks:
· NBMA networks are fully meshed. P2MP networks are not required to be fully meshed.
· NBMA networks require DR and BDR election. P2MP networks do not have DR or BDR.
· On an NBMA network, OSPF packets are unicast, and neighbors are manually configured. On a P2MP network, OSPF packets are multicast by default, and you can configure OSPF to unicast protocol packets.
DR and BDR
DR and BDR mechanism
On a broadcast or NBMA network, any two routers must establish an adjacency to exchange routing information with each other. If n routers are present on the network, n(n-1)/2 adjacencies are established. Any topology change on the network results in an increase in traffic for route synchronization, which consumes a large amount of system and bandwidth resources.
Using the DR and BDR mechanisms can solve this problem.
· DR—Elected to advertise routing information among other routers. If the DR fails, routers on the network must elect another DR and synchronize information with the new DR. Using this mechanism without BDR is time-consuming and is prone to route calculation errors.
· BDR—Elected along with the DR to establish adjacencies with all other routers. If the DR fails, the BDR immediately becomes the new DR, and other routers elect a new BDR.
Routers other than the DR and BDR are called DR Others. They do not establish adjacencies with one another, so the number of adjacencies is reduced.
The role of a router is subnet (or interface) specific. It might be a DR on one interface and a BDR or DR Other on another interface.
As shown in Figure 22, solid lines are Ethernet physical links, and dashed lines represent OSPF adjacencies. With the DR and BDR, only seven adjacencies are established.
Figure 22 DR and BDR in a network
|
NOTE: In OSPF, neighbor and adjacency are different concepts. After startup, OSPF sends a hello packet on each OSPF interface. A receiving router checks parameters in the packet. If the parameters match its own, the receiving router considers the sending router an OSPF neighbor. Two OSPF neighbors establish an adjacency relationship after they synchronize their LSDBs through exchange of DD packets and LSAs. |
DR and BDR election
DR election is performed on broadcast or NBMA networks but not on P2P and P2MP networks.
Routers in a broadcast or NBMA network elect the DR and BDR by router priority and ID. Routers with a router priority value higher than 0 are candidates for DR and BDR election.
The election votes are hello packets. Each router sends the DR elected by itself in a hello packet to all the other routers. If two routers on the network declare themselves as the DR, the router with the higher router priority wins. If router priorities are the same, the router with the higher router ID wins.
If a router with a higher router priority becomes active after DR and BDR election, the router cannot replace the DR or BDR until a new election is performed. Therefore, the DR of a network might not be the router with the highest priority, and the BDR might not be the router with the second highest priority.
Protocols and standards
· RFC 1765, OSPF Database Overflow
· RFC 2328, OSPF Version 2
· RFC 3101, OSPF Not-So-Stubby Area (NSSA) Option
· RFC 3137, OSPF Stub Router Advertisement
· RFC 4811, OSPF Out-of-Band LSDB Resynchronization
· RFC 4812, OSPF Restart Signaling
· RFC 4813, OSPF Link-Local Signaling
OSPF configuration task list
To run OSPF, you must first enable OSPF on the router. Make a proper configuration plan to avoid incorrect settings that can result in route blocking and routing loops.
To configure OSPF, perform the following tasks:
Enabling OSPF
Enable OSPF before you perform other OSPF configuration tasks.
Configuration prerequisites
Configure the link layer protocol and IP addresses for interfaces to ensure IP connectivity between neighboring nodes.
Configuration guidelines
To enable OSPF on an interface, you can enable OSPF on the network where the interface resides or directly enable OSPF on that interface. If you configure both, the latter takes precedence.
You can specify a global router ID, or specify a router ID when you create an OSPF process.
· If you specify a router ID when you create an OSPF process, any two routers in an AS must have different router IDs. A common practice is to specify the IP address of an interface as the router ID.
· If you specify no router ID when you create the OSPF process, the global router ID is used. As a best practice, specify a router ID when you create the OSPF process.
OSPF supports multiple processes and VPNs.
· To run multiple OSPF processes, you must specify an ID for each process. The process IDs take effect locally and has no influence on packet exchange between routers. Two routers with different process IDs can exchange packets.
· You can configure an OSPF process to run in a specified VPN instance. For more information about VPN, see MPLS Configuration Guide.
Enabling OSPF on a network
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. (Optional.) Configure a global router ID. |
router id router-id |
By default, no global router ID is configured. If no global router ID is configured, the highest loopback interface IP address, if any, is used as the router ID. If no loopback interface IP address is available, the highest physical interface IP address is used, regardless of the interface status (up or down). |
3. Enable an OSPF process and enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
By default, OSPF is disabled. |
4. (Optional.) Configure a description for the OSPF process. |
description text |
By default, no description is configured for the OSPF process. As a best practice, configure a description for each OSPF process. |
5. Create an OSPF area and enter OSPF area view. |
area area-id |
By default, no OSPF areas exist. |
6. (Optional.) Configure a description for the area. |
description text |
By default, no description is configured for the area. As a best practice, configure a description for each OSPF area. |
7. Specify a network to enable the interface attached to the network to run the OSPF process in the area. |
network ip-address wildcard-mask |
By default, no network is specified. A network can be added to only one area. |
Enabling OSPF on an interface
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Enable an OSPF process on the interface. |
ospf process-id area area-id [ exclude-subip ] |
By default, OSPF is disabled on an interface. If the specified OSPF process and area do not exist, the command creates the OSPF process and area. Disabling an OSPF process on an interface does not delete the OSPF process or the area. |
Configuring OSPF areas
Before you configure an OSPF area, perform the following tasks:
· Configure IP addresses for interfaces to ensure IP connectivity between neighboring nodes.
· Enable OSPF.
Configuring a stub area
You can configure a non-backbone area at an AS edge as a stub area. To do so, execute the stub command on all routers attached to the area. The routing table size is reduced because Type-5 LSAs will not be flooded within the stub area. The ABR generates a default route into the stub area so all packets destined outside of the AS are sent through the default route.
To further reduce the routing table size and routing information exchanged in the stub area, configure a totally stub area by using the stub no-summary command on the ABR. AS external routes and inter-area routes will not be distributed into the area. All the packets destined outside of the AS or area will be sent to the ABR for forwarding.
A stub or totally stub area cannot have an ASBR because external routes cannot be distributed into the area.
To configure an OSPF stub area:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Enter area view. |
area area-id |
N/A |
4. Configure the area as a stub area. |
stub [ default-route-advertise-always | no-summary ] * |
By default, no stub area is configured. |
5. (Optional.) Set a cost for the default route advertised to the stub area. |
default-cost cost-value |
The default setting is 1. The default-cost cost command takes effect only on the ABR of a stub area or totally stub area. |
Configuring an NSSA area
A stub area cannot import external routes, but an NSSA area can import external routes into the OSPF routing domain while retaining other stub area characteristics.
Do not configure the backbone area as an NSSA area or totally NSSA area.
To configure an NSSA area, configure the nssa command on all the routers attached to the area.
To configure a totally NSSA area, configure the nssa command on all the routers attached to the area and configure the nssa no-summary command on the ABR. The ABR of a totally NSSA area does not advertise inter-area routes into the area.
To configure an NSSA area:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Enter area view. |
area area-id |
N/A |
4. Configure the area as an NSSA area. |
nssa [ default-route-advertise [ cost cost-value | nssa-only | route-policy route-policy-name | type type ] * | no-import-route | no-summary | suppress-fa | [ [ [ translate-always ] [ translate-ignore-checking-backbone ] ] | translate-never ] | translator-stability-interval value ] * |
By default, no area is configured as an NSSA area. |
5. (Optional.) Set a cost for the default route advertised to the NSSA area. |
default-cost cost-value |
The default setting is 1. This command takes effect only on the ABR/ASBR of an NSSA or totally NSSA area. |
Configuring a virtual link
Virtual links are configured for connecting backbone area routers that have no direct physical links.
To configure a virtual link:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Enter area view. |
area area-id |
N/A |
4. Configure a virtual link. |
vlink-peer router-id [ dead seconds | hello seconds | { { hmac-md5 | md5 } key-id { cipher | plain } string | keychain keychain-name | simple { cipher | plain } string } | retransmit seconds | trans-delay seconds ] * |
By default, no virtual links exist. Configure this command on both ends of a virtual link. The hello and dead intervals must be identical on both ends of the virtual link. |
Configuring OSPF network types
OSPF classifies networks into the following types based on the link layer protocol:
· Broadcast—When the link layer protocol is Ethernet or FDDI, OSPF classifies the network type as broadcast by default.
· NBMA—When the link layer protocol is Frame Relay, ATM, or X.25, OSPF classifies the network type as NBMA by default.
· P2P—When the link layer protocol is PPP, LAPB, or HDLC, OSPF classifies the network type as P2P by default.
When you change the network type of an interface, follow these guidelines:
· When an NBMA network becomes fully meshed, change the network type to broadcast to avoid manual configuration of neighbors.
· If any routers in a broadcast network do not support multicasting, change the network type to NBMA.
· An NBMA network must be fully meshed. OSPF requires that an NBMA network be fully meshed. If a network is partially meshed, change the network type to P2MP.
· If a router on an NBMA network has only one neighbor, you can change the network type to P2P to save costs.
Two broadcast-, NBMA-, and P2MP-interfaces can establish a neighbor relationship only when they are on the same network segment.
Configuration prerequisites
Before you configure OSPF network types, perform the following tasks:
· Configure IP addresses for interfaces to ensure IP connectivity between neighboring nodes.
· Enable OSPF.
Configuring the broadcast network type for an interface
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Configure the OSPF network type for the interface as broadcast. |
ospf network-type broadcast |
By default, the network type of an interface depends on the link layer protocol. |
4. (Optional.) Set a router priority for the interface. |
ospf dr-priority priority |
The default router priority is 1. |
Configuring the NBMA network type for an interface
After you configure the network type as NBMA, you must specify neighbors and their router priorities because NBMA interfaces cannot find neighbors by broadcasting hello packets.
To configure the NBMA network type for an interface:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Configure the OSPF network type for the interface as NBMA. |
ospf network-type nbma |
By default, the network type of an interface depends on the link layer protocol. |
4. (Optional.) Set a router priority for the interface. |
ospf dr-priority priority |
The default setting is 1. The router priority configured with this command is for DR election. |
5. Return to system view. |
quit |
N/A |
6. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
7. Specify a neighbor and set its router priority. |
peer ip-address [ dr-priority priority ] |
By default, no neighbor is specified. The priority configured with this command indicates whether a neighbor has the election right or not. If you configure the router priority for a neighbor as 0, the local router determines the neighbor has no election right, and does not send hello packets to this neighbor. However, if the local router is the DR or BDR, it still sends hello packets to the neighbor for neighbor relationship establishment. |
Configuring the P2MP network type for an interface
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Configure the OSPF network type for the interface as P2MP. |
ospf network-type p2mp [ unicast ] |
By default, the network type of an interface depends on the link layer protocol. After you configure the OSPF network type for an interface as P2MP unicast, all packets are unicast over the interface. The interface cannot broadcast hello packets to discover neighbors, so you must manually specify the neighbors. |
4. Return to system view. |
quit |
N/A |
5. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
6. (Optional.) Specify a neighbor and set its router priority. |
peer ip-address [ cost cost-value ] |
By default, no neighbor is specified. This step must be performed if the network type is P2MP unicast, and is optional if the network type is P2MP. |
Configuring the P2P network type for an interface
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Configure the OSPF network type for the interface as P2P. |
ospf network-type p2p [ peer-address-check ] |
By default, the network type of an interface depends on the link layer protocol. |
Configuring OSPF route control
This section describes how to control the advertisement and reception of OSPF routing information, as well as route redistribution from other protocols.
Configuration prerequisites
Before you configure OSPF route control, perform the following tasks:
· Configure IP addresses for interfaces to ensure IP connectivity between neighboring nodes.
· Enable OSPF.
· Configure filters if routing information filtering is needed.
Configuring OSPF route summarization
Route summarization enables an ABR or ASBR to summarize contiguous networks into a single network and advertise the network to other areas.
Route summarization reduces the routing information exchanged between areas and the size of routing tables, and improves routing performance. For example, three internal networks 19.1.1.0/24, 19.1.2.0/24, and 19.1.3.0/24 are available within an area. You can summarize the three networks into network 19.1.0.0/16, and advertise the summary network to other areas.
Configuring route summarization on an ABR
After you configure a summary route on an ABR, the ABR generates a summary LSA instead of specific LSAs. The scale of LSDBs on routers in other areas and the influence of topology changes are reduced.
To configure route summarization on an ABR:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Enter OSPF area view. |
area area-id |
N/A |
4. Configure ABR route summarization. |
abr-summary ip-address { mask-length | mask } [ advertise | not-advertise ] [ cost cost-value ] |
By default, route summarization is not configured on an ABR. |
Configuring route summarization on an ASBR
Perform this task to enable an ASBR to summarize external routes within the specified address range into a single route. The ASBR advertises only the summary route to reduce the number of LSAs in the LSDB.
An ASBR can summarize routes in the following LSAs:
· Type-5 LSAs.
· Type-7 LSAs in an NSSA area.
· Type-5 LSAs translated by the ASBR (also an ABR) from Type-7 LSAs in an NSSA area.
If the ASBR (ABR) is not a translator, it cannot summarize routes in Type-5 LSAs translated from Type-7 LSAs.
To configure route summarization on an ASBR:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
asbr-summary ip-address { mask-length | mask } [ cost cost-value | not-advertise | nssa-only | tag tag ] * |
By default, route summarization is not configured on an ASBR. |
Configuring received OSPF route filtering
Perform this task to filter routes calculated using received LSAs.
The following filtering methods are available:
· Use an ACL or IP prefix list to filter routing information by destination address.
· Use the gateway keyword to filter routing information by next hop.
· Use an ACL or IP prefix list to filter routing information by destination address. At the same time use the gateway keyword to filter routing information by next hop.
· Use a routing policy to filter routing information.
To configure OSPF to filter routes calculated using received LSAs:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Configure OSPF to filter routes calculated using received LSAs. |
filter-policy { ipv4-acl-number [ gateway prefix-list-name ] | gateway prefix-list-name | prefix-list prefix-list-name [ gateway prefix-list-name ] | route-policy route-policy-name } import |
By default, OSPF accepts all routes calculated using received LSAs. |
Configuring Type-3 LSA filtering
Perform this task to filter Type-3 LSAs advertised to an area on an ABR.
To configure Type-3 LSA filtering:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Enter area view. |
area area-id |
N/A |
4. Configure Type-3 LSA filtering. |
filter { ipv4-acl-number | prefix-list prefix-list-name | route-policy route-policy-name } { export | import } |
By default, the ABR does not filter Type-3 LSAs. |
Setting an OSPF cost for an interface
Set an OSPF cost for an interface by using either of the following methods:
· Set the cost value in interface view.
· Set a bandwidth reference value for the interface. OSPF computes the cost with this formula: Interface OSPF cost = Bandwidth reference value (100 Mbps) / Expected interface bandwidth (Mbps). The expected bandwidth of an interface is configured with the bandwidth command (see Interface Command Reference).
? If the calculated cost is greater than 65535, the value of 65535 is used. If the calculated cost is less than 1, the value of 1 is used.
? If no cost or bandwidth reference value is configured for an interface, OSPF computes the interface cost based on the interface bandwidth and default bandwidth reference value.
To set an OSPF cost for an interface:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Set an OSPF cost for the interface. |
ospf cost cost-value |
By default, the OSPF cost is calculated according to the interface bandwidth. For a loopback interface, the OSPF cost is 0 by default. |
To set a bandwidth reference value:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Set a bandwidth reference value. |
bandwidth-reference value |
The default setting is 100 Mbps. |
Setting the maximum number of ECMP routes
Perform this task to implement load sharing over ECMP routes.
To set the maximum number of ECMP routes:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Set the maximum number of ECMP routes. |
maximum load-balancing number |
By default, the maximum number of ECMP routes equals the maximum number of ECMP routes supported by the system. |
Setting OSPF preference
A router can run multiple routing protocols, and each protocol is assigned a preference. If multiple routes are available to the same destination, the one with the highest protocol preference is selected as the best route.
To set OSPF preference:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Set a preference for OSPF. |
preference [ ase ] { preference | route-policy route-policy-name } * |
By default, the preference of OSPF internal routes is 10 and the preference of OSPF external routes is 150. |
Configuring discard routes for summary networks
Perform this task on an ABR or ASBR to specify whether to generate discard routes for summary networks. You can also specify a preference for the discard routes.
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Configure discard routes for summary networks. |
discard-route { external { preference | suppression } | internal { preference | suppression } } * |
By default: · The ABR or ASBR generates discard routes for summary networks. · The preference of discard routes is 255. |
Configuring OSPF route redistribution
On a router running OSPF and other routing protocols, you can configure OSPF to redistribute static routes, direct routes, or routes from other protocols, such as RIP, IS-IS, and BGP. OSPF advertises the routes in Type-5 LSAs or Type-7 LSAs. In addition, you can configure OSPF to filter redistributed routes so that OSPF advertises only permitted routes.
|
IMPORTANT: The import-route bgp command redistributes only EBGP routes. Because the import-route bgp allow-ibgp command redistributes both EBGP and IBGP routes, and might cause routing loops, use it with caution. |
Redistributing routes from another routing protocol
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Configure OSPF to redistribute routes from another routing protocol. |
import-route protocol [ as-number ] [ process-id | all-processes | allow-ibgp ] [ allow-direct | cost cost-value | nssa-only | route-policy route-policy-name | tag tag | type type ] * |
By default, no route redistribution is configured. This command redistributes only active routes. To view information about active routes, use the display ip routing-table protocol command. |
4. (Optional.) Configure OSPF to filter redistributed routes. |
filter-policy { ipv4-acl-number | prefix-list prefix-list-name } export [ protocol [ process-id ] ] |
By default, OSPF accepts all redistributed routes. |
Redistributing a default route
The import-route command cannot redistribute a default external route. Perform this task to redistribute a default route.
To redistribute a default route:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Redistribute a default route. |
default-route-advertise [ [ always | permit-calculate-other ] | cost cost-value | route-policy route-policy-name | type type ] * default-route-advertise [ summary cost cost-value ] |
By default, no default route is redistributed. This command is applicable only to VPNs. The PE router advertises a default route in a Type-3 LSA to a CE router. |
Configuring default parameters for redistributed routes
Perform this task to configure default parameters for redistributed routes, including cost, tag, and type. Tags identify information about protocols. For example, when redistributing BGP routes, OSPF uses tags to identify AS IDs.
To configure the default parameters for redistributed routes:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Configure the default parameters for redistributed routes (cost, upper limit, tag, and type). |
default { cost cost-value | tag tag | type type } * |
By default, the cost is 1, the tag is 1, and the type is Type-2. |
Advertising a host route
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Enter area view. |
area area-id |
N/A |
4. Advertise a host route. |
host-advertise ip-address cost |
By default, no host route is advertised. |
Excluding interfaces in an OSPF area from the base topology
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Enter area view. |
area area-id |
N/A |
4. Exclude interfaces in the OSPF area from the base topology. |
capability default-exclusion |
By default, interfaces in an OSPF area belong to the base topology. |
Tuning and optimizing OSPF networks
You can use one of the following methods to optimize an OSPF network:
· Change OSPF packet timers to adjust the convergence speed and network load. On low-speed links, consider the delay time for sending LSAs.
· Change the SPF calculation interval to reduce resource consumption caused by frequent network changes.
· Configure OSPF authentication to improve security.
Configuration prerequisites
Before you configure OSPF network optimization, perform the following tasks:
· Configure IP addresses for interfaces to ensure IP connectivity between neighboring nodes.
· Enable OSPF.
Setting OSPF timers
An OSPF interface includes the following timers:
· Hello timer—Interval for sending hello packets. It must be identical on OSPF neighbors.
· Poll timer—Interval for sending hello packets to a neighbor that is down on the NBMA network.
· Dead timer—Interval within which if the interface does not receive any hello packet from the neighbor, it declares the neighbor is down.
· LSA retransmission timer—Interval within which if the interface does not receive any acknowledgment packets after sending an LSA to the neighbor, it retransmits the LSA.
To set OSPF timers:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Set the hello interval. |
ospf timer hello seconds |
By default: · The hello interval on P2P and broadcast interfaces is 10 seconds. · The hello interval on P2MP and NBMA interfaces is 30 seconds. The default hello interval is restored when the network type for an interface is changed. |
4. Set the poll interval. |
ospf timer poll seconds |
The default setting is 120 seconds. The poll interval is a minimum of four times the hello interval. |
5. Set the dead interval. |
ospf timer dead seconds |
By default: · The dead interval on P2P and broadcast interfaces is 40 seconds. · The dead interval on P2MP and NBMA interfaces is 120 seconds. The dead interval must be a minimum of four times the hello interval on an interface. The default dead interval is restored when the network type for an interface is changed. |
6. Set the retransmission interval. |
ospf timer retransmit interval |
The default setting is 5 seconds. A retransmission interval setting that is too small can cause unnecessary LSA retransmissions. This interval is typically set bigger than the round-trip time of a packet between two neighbors. |
Setting LSA transmission delay
To avoid LSAs from aging out during transmission, set an LSA retransmission delay especially for low speed links.
To set the LSA transmission delay on an interface:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Set the LSA transmission delay. |
ospf trans-delay seconds |
The default setting is 1 second. |
Setting SPF calculation interval
LSDB changes result in SPF calculations. When the topology changes frequently, a large amount of network and router resources are occupied by SPF calculation. You can adjust the SPF calculation interval to reduce the impact.
For a stable network, the minimum interval is used. If network changes become frequent, the SPF calculation interval is incremented by the incremental interval × 2n-2 for each calculation until the maximum interval is reached. The value n is the number of calculation times.
To set the SPF calculation interval:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Set the SPF calculation interval. |
spf-schedule-interval maximum-interval [ minimum-interval [ incremental-interval ] ] |
By default: · The maximum interval is 5 seconds. · The minimum interval is 50 milliseconds. · The incremental interval is 200 milliseconds. |
Setting the LSA arrival interval
If OSPF receives an LSA that has the same LSA type, LS ID, and router ID as the previously received LSA within the LSA arrival interval, OSPF discards the LSA to save bandwidth and route resources.
To set the LSA arrival interval:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Set the LSA arrival interval. |
lsa-arrival-interval interval |
The default setting is 1000 milliseconds. Make sure this interval is smaller than or equal to the interval set with the lsa-generation-interval command. |
Setting the LSA generation interval
Adjust the LSA generation interval to protect network resources and routers from being overwhelmed by LSAs at the time of frequent network changes.
For a stable network, the minimum interval is used. If network changes become frequent, the LSA generation interval is incremented by the incremental interval × 2n-2 for each generation until the maximum interval is reached. The value n is the number of generation times.
To set the LSA generation interval:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Set the LSA generation interval. |
lsa-generation-interval maximum-interval [ minimum-interval [ incremental-interval ] ] |
By default: · The maximum interval is 5 seconds. · The minimum interval is 50 milliseconds. · The incremental interval is 200 milliseconds. |
Disabling interfaces from receiving and sending OSPF packets
To enhance OSPF adaptability and reduce resource consumption, you can set an OSPF interface to "silent." A silent OSPF interface blocks OSPF packets and cannot establish any OSPF neighbor relationship. However, other interfaces on the router can still advertise direct routes of the interface in Router LSAs.
To disable interfaces from receiving and sending routing information:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Disable interfaces from receiving and sending OSPF packets. |
silent-interface { interface-type interface-number | all } |
By default, an OSPF interface can receive and send OSPF packets. The silent-interface command disables only the interfaces associated with the current process rather than other processes. Multiple OSPF processes can disable the same interface from receiving and sending OSPF packets. |
Configuring stub routers
A stub router is used for traffic control. It reports its status as a stub router to neighboring OSPF routers. The neighboring routers can have a route to the stub router, but they do not use the stub router to forward data.
Router LSAs from the stub router might contain different link type values. A value of 3 means a link to a stub network, and the cost of the link will not be changed by default. To set the cost of the link to 65535, specify the include-stub keyword in the stub-router command. A value of 1, 2 or 4 means a point-to-point link, a link to a transit network, or a virtual link. On such links, a maximum cost value of 65535 is used. Neighbors do not send packets to the stub router as long as they have a route with a smaller cost.
To configure a router as a stub router:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Configure the router as a stub router. |
stub-router [ external-lsa [ max-metric-value ] | include-stub | on-startup { seconds | wait-for-bgp [ seconds ] } | summary-lsa [ max-metric-value ] ] * |
By default, the router is not configured as a stub router. A stub router is not related to a stub area. |
Configuring OSPF authentication
Perform this task to configure OSPF area and interface authentication.
OSPF adds the configured key into sent packets, and uses the key to authenticate received packets. Only packets that pass the authentication can be received. If a packet fails the authentication, the OSPF neighbor relationship cannot be established.
If you configure OSPF authentication for both an area and an interface in that area, the interface uses the OSPF authentication configured on it.
Configuring OSPF area authentication
You must configure the same authentication mode and key on all the routers in an area.
To configure OSPF area authentication:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Enter area view. |
area area-id |
N/A |
4. Configure area authentication mode. |
·
Configure MD5 authentication: ·
Configure simple authentication: ·
Configure keychain authentication: |
By default, no authentication is configured. For information about keychains, see Security Configuration Guide. |
Configuring OSPF interface authentication
You must configure the same authentication mode and key on both the local interface and its peer interface.
To configure OSPF interface authentication:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Configure interface authentication mode. |
·
Configure simple authentication: ·
Configure MD5 authentication: ·
Configure keychain authentication: |
By default, no authentication is configured. For information about keychain, see Security Configuration Guide. |
Adding the interface MTU into DD packets
By default, an OSPF interface adds a value of 0 into the interface MTU field of a DD packet rather than the actual interface MTU. You can enable an interface to add its MTU into DD packets.
To add the interface MTU into DD packets:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Enable the interface to add its MTU into DD packets. |
ospf mtu-enable |
By default, the interface adds an MTU value of 0 into DD packets. |
Setting the DSCP value for outgoing OSPF packets
The DSCP value specifies the precedence of outgoing packets.
To set the DSCP value for OSPF packets:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Set the DSCP value for outgoing OSPF packets. |
dscp dscp-value |
By default, the DSCP value for outgoing OSPF packets is 48. |
Setting the maximum number of external LSAs in LSDB
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Set the maximum number of external LSAs in the LSDB. |
lsdb-overflow-limit number |
By default, the maximum number of external LSAs in the LSDB is not limited. |
Setting OSPF exit overflow interval
When the number of LSAs in the LSDB exceeds the upper limit, the LSDB is in an overflow state. To save resources, OSPF does not receive any external LSAs and deletes the external LSAs generated by itself when in this state.
Perform this task to configure the interval that OSPF exits overflow state.
To set the OSPF exit overflow interval:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Set the OSPF exit overflow interval. |
lsdb-overflow-interval interval |
The default setting is 300 seconds. The value of 0 indicates that OSPF does not exit overflow state. |
Enabling compatibility with RFC 1583
RFC 1583 specifies a different method than RFC 2328 for selecting the optimal route to a destination in another AS. When multiple routes are available to the ASBR, OSPF selects the optimal route by using the following procedure:
1. Selects the route with the highest preference.
? If RFC 2328 is compatible with RFC 1583, all these routes have equal preference.
? If RFC 2328 is not compatible with RFC 1583, the intra-area route in a non-backbone area is preferred to reduce the burden of the backbone area. The inter-area route and intra-area route in the backbone area have equal preference.
2. Selects the route with the lower cost if two routes have equal preference.
3. Selects the route with the larger originating area ID if two routes have equal cost.
To avoid routing loops, set identical RFC 1583-compatibility on all routers in a routing domain.
To enable compatibility with RFC 1583:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Enable compatibility with RFC 1583. |
rfc1583 compatible |
By default, compatibility with RFC 1583 is enabled. |
Logging neighbor state changes
Perform this task to enable output of neighbor state change logs to the information center. The information center processes the logs according to user-defined output rules (whether and where to output logs). For more information about the information center, see Network Management and Monitoring Configuration Guide.
To enable the logging of neighbor state changes:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Enable the logging of neighbor state changes. |
log-peer-change |
By default, this feature is enabled. |
Configuring OSPF network management
This task involves the following configurations:
· Bind an OSPF process to MIB so that you can use network management software to manage the specified OSPF process.
· Enable SNMP notifications for OSPF to report important events.
· Configure the SNMP notification output interval and the maximum number of SNMP notifications that can be output at each interval.
To report critical OSPF events to an NMS, enable SNMP notifications for OSPF. For SNMP notifications to be sent correctly, you must also configure SNMP on the device. For more information about SNMP configuration, see the network management and monitoring configuration guide for the device.
To configure OSPF network management:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Bind OSPF MIB to an OSPF process. |
ospf mib-binding process-id |
By default, OSPF MIB is bound to the process with the smallest process ID. |
3. Enable SNMP notifications for OSPF. |
snmp-agent trap enable ospf [ authentication-failure | bad-packet | config-error | grhelper-status-change | grrestarter-status-change | if-state-change | lsa-maxage | lsa-originate | lsdb-approaching-overflow | lsdb-overflow | neighbor-state-change | nssatranslator-status-change | retransmit | virt-authentication-failure | virt-bad-packet | virt-config-error | virt-retransmit | virtgrhelper-status-change | virtif-state-change | virtneighbor-state-change ] * |
By default, SNMP notifications for OSPF are enabled. |
4. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
5. Configure the SNMP notification output interval and the maximum number of SNMP notifications that can be output at each interval. |
snmp trap rate-limit interval trap-interval count trap-number |
By default, OSPF outputs a maximum of seven SNMP notifications within 10 seconds. |
Setting the LSU transmit rate
Sending large numbers of LSU packets affects router performance and consumes a large amount of network bandwidth. You can configure the router to send LSU packets at an interval and to limit the maximum number of LSU packets sent out of an OSPF interface at each interval.
To set the LSU transmit rate:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Set the LSU transmit rate. |
transmit-pacing interval interval count count |
By default, an OSPF interface sends a maximum of three LSU packets every 20 milliseconds. |
Setting the maximum length of OSPF packets that can be sent by an interface
In some scenarios, for example, when you establish OSPF neighbors over a tunnel, you can perform this task to prevent OSPF packet fragmentation on the outgoing tunnel interface. Make sure the maximum length of the OSPF packets plus the encapsulated header length is no greater than the outgoing tunnel interface's MTU. For more information, see Layer 3—IP Services Configuration Guide.
To set the maximum length of OSPF packets that can be sent by an interface:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Set the maximum length of OSPF packets that can be sent by an interface. |
ospf packet-size value |
By default, the maximum length of OSPF packets that an interface can send equals the interface's MTU. |
Enabling OSPF ISPF
When the topology changes, Incremental Shortest Path First (ISPF) computes only the affected part of the SPT, instead of the entire SPT.
To enable OSPF ISPF:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Enable OSPF ISPF. |
ispf enable |
By default, OSPF ISPF is enabled. |
Configuring prefix suppression
By default, an OSPF interface advertises all of its prefixes in LSAs. To speed up OSPF convergence, you can suppress interfaces from advertising all of their prefixes. This feature helps improve network security by preventing IP routing to the suppressed networks.
When prefix suppression is enabled:
· On P2P and P2MP networks, OSPF does not advertise Type-3 links in Type-1 LSAs. Other routing information can still be advertised to ensure traffic forwarding.
· On broadcast and NBMA networks, the DR generates Type-2 LSAs with a mask length of 32 to suppress network routes. Other routing information can still be advertised to ensure traffic forwarding. If no neighbors exist, the DR does not advertise the primary IP addresses of interfaces in Type-1 LSAs.
|
IMPORTANT: As a best practice, configure prefix suppression on all OSPF routers if you want to use prefix suppression. |
Configuring prefix suppression for an OSPF process
Enabling prefix suppression for an OSPF process does not suppress the prefixes of secondary IP addresses, loopback interfaces, and passive interfaces. To suppress the prefixes of loopback interfaces and passive interfaces, enable prefix suppression on the interfaces.
To configure prefix suppression for an OSPF process:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Enable prefix suppression for the OSPF process. |
prefix-suppression |
By default, prefix suppression is disabled for an OSPF process. |
Configuring prefix suppression for an interface
Interface prefix suppression does not suppress prefixes of secondary IP addresses.
To configure interface prefix suppression:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Enable prefix suppression for the interface. |
ospf prefix-suppression [ disable ] |
By default, prefix suppression is disabled on an interface. |
Configuring prefix prioritization
This feature enables the device to install prefixes in descending priority order: critical, high, medium, and low. The prefix priorities are assigned through routing policies. When a route is assigned multiple prefix priorities, the route uses the highest priority.
By default, the 32-bit OSPF host routes have a medium priority and other routes a low priority.
To configure prefix prioritization:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Enable prefix prioritization. |
prefix-priority route-policy route-policy-name |
By default, prefix prioritization is disabled. |
Configuring OSPF PIC
Prefix Independent Convergence (PIC) enables the device to speed up network convergence by ignoring the number of prefixes.
When both OSPF PIC and OSPF FRR are configured, OSPF FRR takes effect.
OSPF PIC applies only to inter-area routes and external routes.
Enabling OSPF PIC
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Enable PIC for OSPF. |
pic [ additional-path-always ] |
By default, OSPF PIC is enabled. |
Configuring BFD for OSPF PIC
By default, OSPF PIC does not use BFD to detect primary link failures. To speed up OSPF convergence, enable BFD for OSPF PIC to detect the primary link failures.
To configure BFD control packet mode for OSPF PIC:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Enable BFD control packet mode for OSPF PIC. |
ospf primary-path-detect bfd ctrl |
By default, BFD control packet mode for OSPF PIC is disabled. |
To configure BFD echo packet mode for OSPF PIC:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Configure the source IP address of BFD echo packets. |
bfd echo-source-ip ip-address |
By default, the source IP address of BFD echo packets is not configured. The source IP address cannot be on the same network segment as any local interface's IP address. For more information about this command, see High Availability Command Reference. |
3. Enter interface view. |
interface interface-type interface-number |
N/A |
4. Enable BFD echo packet mode for OSPF PIC. |
ospf primary-path-detect bfd echo |
By default, BFD echo packet mode for OSPF PIC is disabled. |
Setting the number of OSPF logs
OSPF logs include LSA aging logs, route calculation logs, and neighbor logs.
To set the number of OSPF logs:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Set the number of OSPF logs. |
event-log { lsa-flush | peer | spf } size count |
By default, the number of LSA aging logs, route calculation logs, or neighbor logs is 10. |
Filtering outbound LSAs on an interface
To reduce the LSDB size for the neighbor and save bandwidth, you can perform this task on an interface to filter LSAs to be sent to the neighbor.
To filter outbound LSAs on an interface:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Filter outbound LSAs on the interface. |
ospf database-filter { all | { ase [ acl ipv4-acl-number ] | nssa [ acl ipv4-acl-number ] | summary [ acl ipv4-acl-number ] } * } |
By default, the outbound LSAs are not filtered on the interface. |
Filtering LSAs for the specified neighbor
On an P2MP network, a router might have multiple OSPF neighbors with the P2MP type. Perform this task to prevent the router from sending LSAs to the specified neighbor.
To filter LSAs for the specified neighbor:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Filter LSAs for the specified neighbor. |
database-filter peer ip-address { all | { ase [ acl ipv4-acl-number ] | nssa [ acl ipv4-acl-number ] | summary [ acl ipv4-acl-number ] } * } |
By default, the LSAs for the specified neighbor are not filtered. |
Configuring GTSM for OSPF
The Generalized TTL Security Mechanism (GTSM) protects the device by comparing the TTL value in the IP header of incoming OSPF packets against a valid TTL range. If the TTL value is within the valid TTL range, the packet is accepted. If not, the packet is discarded.
The valid TTL range is from 255 – the configured hop count + 1 to 255.
When GTSM is configured, the OSPF packets sent by the device have a TTL of 255.
GTSM checks OSPF packets from common neighbors and virtual link neighbors. It does not check OSPF packets from sham link neighbors. For information about GTSM for OSPF sham links, see MPLS Configuration Guide.
You can configure GTSM in OSPF area view or interface view.
· The configuration in OSPF area view applies to all OSPF interfaces in the area.
· The configuration in interface view takes precedence over OSPF area view.
|
IMPORTANT: To use GTSM, you must configure GTSM on both the local and peer devices. You can specify different hop-count values for them. |
To configure GTSM in OSPF area view:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Enter OSPF area view. |
area area-id |
N/A |
4. Enable GTSM for the OSPF area. |
ttl-security [ hops hop-count ] |
By default, GTSM is disabled for the OSPF area. |
To configure GTSM in interface view:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Enable GTSM for the interface. |
ospf ttl-security [ hops hop-count | disable ] |
By default, GTSM is disabled for the interface. |
Configuring OSPF GR
GR ensures forwarding continuity when a routing protocol restarts or an active/standby switchover occurs.
Two routers are required to complete a GR process. The following are router roles in a GR process:
· GR restarter—Graceful restarting router. It must have GR capability.
· GR helper—A neighbor of the GR restarter. It helps the GR restarter to complete the GR process.
OSPF GR has the following types:
· IETF GR—Uses Opaque LSAs to implement GR.
· Non-IETF GR—Uses link local signaling (LLS) to advertise GR capability and uses out of band synchronization to synchronize the LSDB.
A device can act as a GR restarter and GR helper at the same time.
Configuring OSPF GR restarter
You can configure the IETF or non-IETF OSPF GR restarter.
|
IMPORTANT: You cannot enable OSPF NSR on a device that acts as GR restarter. |
Configuring the IETF OSPF GR restarter
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enable OSPF and enter its view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Enable opaque LSA reception and advertisement capability. |
opaque-capability enable |
By default, opaque LSA reception and advertisement capability is enabled. |
4. Enable the IETF GR. |
graceful-restart ietf [ global | planned-only ] * |
By default, the IETF GR capability is disabled. |
5. (Optional.) Set the GR interval. |
graceful-restart interval interval |
By default, the GR interval is 120 seconds. |
Configuring the non-IETF OSPF GR restarter
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enable OSPF and enter its view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Enable the link-local signaling capability. |
enable link-local-signaling |
By default, the link-local signaling capability is disabled. |
4. Enable the out-of-band re-synchronization capability. |
enable out-of-band-resynchronization |
By default, the out-of-band re-synchronization capability is disabled. |
5. Enable non-IETF GR. |
graceful-restart [ nonstandard ] [ global | planned-only ] * |
By default, non-IETF GR capability is disabled. |
6. (Optional.) Set the GR interval. |
graceful-restart interval interval |
By default, the GR interval is 120 seconds. |
Configuring OSPF GR helper
You can configure the IETF or non-IETF OSPF GR helper.
Configuring the IETF OSPF GR helper
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enable OSPF and enter its view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Enable opaque LSA reception and advertisement capability. |
opaque-capability enable |
By default, opaque LSA reception and advertisement capability is enabled. |
4. (Optional.) Enable GR helper capability. |
graceful-restart helper enable [ planned-only ] |
By default, GR helper capability is enabled. |
5. (Optional.) Enable strict LSA checking for the GR helper. |
graceful-restart helper strict-lsa-checking |
By default, strict LSA checking for the GR helper is disabled. |
Configuring the non-IETF OSPF GR helper
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enable OSPF and enter its view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Enable the link-local signaling capability. |
enable link-local-signaling |
By default, the link-local signaling capability is disabled. |
4. Enable the out-of-band re-synchronization capability. |
enable out-of-band-resynchronization |
By default, the out-of-band re-synchronization capability is disabled. |
5. (Optional.) Enable GR helper. |
graceful-restart helper enable |
By default, GR helper is enabled. |
6. (Optional.) Enable strict LSA checking for the GR helper. |
graceful-restart helper strict-lsa-checking |
By default, strict LSA checking for the GR helper is disabled. |
Triggering OSPF GR
OSPF GR is triggered by an active/standby switchover or when the following command is executed.
To trigger OSPF GR, perform the following command in user view:
Task |
Command |
Trigger OSPF GR. |
reset ospf [ process-id ] process graceful-restart |
Configuring OSPF NSR
Nonstop routing (NSR) backs up OSPF link state information from the active process to the standby process. After an active/standby switchover, NSR can complete link state recovery and route regeneration without tearing down adjacencies or impacting forwarding services.
NSR does not require the cooperation of neighboring devices to recover routing information, and it is typically used more often than GR.
|
IMPORTANT: A device that has OSPF NSR enabled cannot act as GR restarter. |
To enable OSPF NSR:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
non-stop-routing |
By default, OSPF NSR is disabled. This command takes effect only for the current process. As a best practice, enable OSPF NSR for each process if multiple OSPF processes exist. |
Configuring BFD for OSPF
OSPF supports the following BFD detection modes:
· Bidirectional control detection—Requires BFD configuration to be made on both OSPF routers on the link.
· Single-hop echo detection—Requires BFD configuration to be made on one OSPF router on the link.
Configuring bidirectional control detection
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Enable BFD bidirectional control detection. |
ospf bfd enable |
By default, BFD bidirectional control detection is disabled. Both ends of a BFD session must be on the same network segment and in the same area. |
Configuring single-hop echo detection
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Configure the source address of echo packets. |
bfd echo-source-ip ip-address |
By default, the source address of echo packets is not configured. |
3. Enter interface view. |
interface interface-type interface-number |
N/A |
4. Enable BFD single-hop echo detection. |
ospf bfd enable echo |
By default, BFD single-hop echo detection is disabled. |
Configuring OSPF FRR
A link or router failure on a path can cause packet loss and even routing loop until OSPF completes routing convergence based on the new network topology. FRR enables fast rerouting to minimize the impact of link or node failures.
Figure 23 Network diagram for OSPF FRR
As shown in Figure 23, configure FRR on Router B by using a routing policy to specify a backup next hop. When the primary link fails, OSPF directs packets to the backup next hop. At the same time, OSPF calculates the shortest path based on the new network topology. It forwards packets over the path after network convergence.
You can configure OSPF FRR to calculate a backup next hop by using the loop free alternate (LFA) algorithm, or specify a backup next hop by using a routing policy.
Configuration prerequisites
Before you configure OSPF FRR, perform the following tasks:
· Configure IP addresses for interfaces to ensure IP connectivity between neighboring nodes.
· Enable OSPF.
Configuration guidelines
· Do not use the fast-reroute lfa command together with the vlink-peer command.
· When both OSPF PIC and OSPF FRR are configured, OSPF FRR takes effect.
Configuration procedure
Configuring OSPF FRR to calculate a backup next hop using the LFA algorithm
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. (Optional.) Enable LFA on an interface. |
ospf fast-reroute lfa-backup |
By default, the interface is enabled with LFA and it can be selected as a backup interface. |
4. Return to system view. |
quit |
N/A |
5. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
6. Enable OSPF FRR to calculate a backup next hop by using the LFA algorithm. |
fast-reroute lfa [ abr-only ] |
By default, OSPF FRR is disabled. If abr-only is specified, the route to the ABR is selected as the backup path. |
Configuring OSPF FRR to specify a backup next hop using a routing policy
Before you perform this task, use the apply fast-reroute backup-interface command to specify a backup next hop in the routing policy to be used. For more information about the apply fast-reroute backup-interface command and routing policy configuration, see "Configuring routing policies."
To configure OSPF FRR to specify a backup next hop using a routing policy:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Enable OSPF FRR to specify a backup next hop by using a routing policy. |
fast-reroute route-policy route-policy-name |
By default, OSPF FRR is disabled. |
Configuring BFD for OSPF FRR
By default, OSPF FRR does not use BFD to detect primary link failures. To speed up OSPF convergence, enable BFD for OSPF FRR to detect primary link failures.
To configure BFD control packet mode for OSPF FRR:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Enable BFD control packet mode for OSPF FRR. |
ospf primary-path-detect bfd ctrl |
By default, BFD control packet mode for OSPF FRR is disabled. |
To configure BFD echo packet mode for OSPF FRR:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Configure the source IP address of BFD echo packets. |
bfd echo-source-ip ip-address |
By default, the source IP address of BFD echo packets is not configured. The source IP address cannot be on the same network segment as any local interface's IP address. For more information about this command, see High Availability Command Reference. |
3. Enter interface view. |
interface interface-type interface-number |
N/A |
4. Enable BFD echo packet mode for OSPF FRR. |
ospf primary-path-detect bfd echo |
By default, BFD echo packet mode for OSPF FRR is disabled. |
Advertising OSPF link state information to BGP
After the device advertises OSPF link state information to BGP, BGP can advertise the information for intended applications. For more information about BGP LS, see "Configuring BGP."
To advertise OSPF link state information to BGP:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPF view. |
ospf [ process-id | router-id router-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Advertise OSPF link state information to BGP. |
distribute bgp-ls |
By default, the device does not advertise OSPF link state information to BGP. |
Displaying and maintaining OSPF
Execute display commands in any view and reset commands in user view.
Task |
Command |
Display OSPF process information. |
display ospf [ process-id ] [ verbose ] |
Display OSPF GR information. |
display ospf [ process-id ] graceful-restart [ verbose ] |
Display OSPF FRR backup next hop information. |
display ospf [ process-id ] [ area area-id ] fast-reroute lfa-candidate |
Display OSPF LSDB information. |
display ospf [ process-id ] lsdb [ brief | originate-router advertising-router-id | self-originate ] display ospf [ process-id ] lsdb { opaque-as | ase } [ link-state-id ] [ originate-router advertising-router-id | self-originate ] display ospf [ process-id ] [ area area-id ] lsdb { asbr | network | nssa | opaque-area | opaque-link | router | summary } [ link-state-id ] [ originate-router advertising-router-id | self-originate ] |
Display OSPF next hop information. |
display ospf [ process-id ] nexthop |
Display OSPF NSR information. |
display ospf [ process-id ] non-stop-routing status |
Display OSPF neighbor information. |
display ospf [ process-id ] peer [ verbose ] [ interface-type interface-number ] [ neighbor-id ] |
Display neighbor statistics for OSPF areas. |
display ospf [ process-id ] peer statistics |
Display OSPF routing table information. |
display ospf [ process-id ] routing [ ip-address { mask-length | mask } ] [ interface interface-type interface-number ] [ nexthop nexthop-address ] [ verbose ] |
Display OSPF topology information. |
display ospf [ process-id ] [ area area-id ] spf-tree [ verbose ] |
Display OSPF statistics. |
display ospf [ process-id ] statistics [ error | packet [ interface-type interface-number ] ] |
Display OSPF virtual link information. |
display ospf [ process-id ] vlink |
Display OSPF request queue information. |
display ospf [ process-id ] request-queue [ interface-type interface-number ] [ neighbor-id ] |
Display OSPF retransmission queue information. |
display ospf [ process-id ] retrans-queue [ interface-type interface-number ] [ neighbor-id ] |
Display OSPF ABR and ASBR information. |
display ospf [ process-id ] abr-asbr [ verbose ] |
Display summary route information on the OSPF ABR. |
display ospf [ process-id ] [ area area-id ] abr-summary [ ip-address { mask-length | mask } ] [ verbose ] |
Display OSPF interface information. |
display ospf [ process-id ] interface [ interface-type interface-number | verbose ] |
Display OSPF log information. |
display ospf [ process-id ] event-log { lsa-flush | peer | spf } |
Display OSPF ASBR route summarization information. |
display ospf [ process-id ] asbr-summary [ ip-address { mask-length | mask } ] |
Display the global route ID. |
display router id |
Clear OSPF statistics. |
reset ospf [ process-id ] statistics |
Clear OSPF log information. |
reset ospf [ process-id ] event-log [ lsa-flush | peer | spf ] |
Restart an OSPF process. |
reset ospf [ process-id ] process [ graceful-restart ] |
Re-enable OSPF route redistribution. |
reset ospf [ process-id ] redistribution |
OSPF configuration examples
Basic OSPF configuration example
Network requirements
As shown in Figure 24:
· Enable OSPF on all switches, and split the AS into three areas.
· Configure Switch A and Switch B as ABRs.
Configuration procedure
1. Configure IP addresses for interfaces. (Details not shown.)
2. Enable OSPF:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] router id 10.2.1.1
[SwitchA] ospf
[SwitchA-ospf-1] area 0
[SwitchA-ospf-1-area-0.0.0.0] network 10.1.1.0 0.0.0.255
[SwitchA-ospf-1-area-0.0.0.0] quit
[SwitchA-ospf-1] area 1
[SwitchA-ospf-1-area-0.0.0.1] network 10.2.1.0 0.0.0.255
[SwitchA-ospf-1-area-0.0.0.1] quit
[SwitchA-ospf-1] quit
# Configure Switch B.
<SwitchB> system-view
[SwitchB] router id 10.3.1.1
[SwitchB] ospf
[SwitchB-ospf-1] area 0
[SwitchB-ospf-1-area-0.0.0.0] network 10.1.1.0 0.0.0.255
[SwitchB-ospf-1-area-0.0.0.0] quit
[SwitchB-ospf-1] area 2
[SwitchB-ospf-1-area-0.0.0.2] network 10.3.1.0 0.0.0.255
[SwitchB-ospf-1-area-0.0.0.2] quit
[SwitchB-ospf-1] quit
# Configure Switch C.
<SwitchC> system-view
[SwitchC] router id 10.4.1.1
[SwitchC] ospf
[SwitchC-ospf-1] area 1
[SwitchC-ospf-1-area-0.0.0.1] network 10.2.1.0 0.0.0.255
[SwitchC-ospf-1-area-0.0.0.1] network 10.4.1.0 0.0.0.255
[SwitchC-ospf-1-area-0.0.0.1] quit
[SwitchC-ospf-1] quit
# Configure Switch D.
<SwitchD> system-view
[SwitchD] router id 10.5.1.1
[SwitchD] ospf
[SwitchD-ospf-1] area 2
[SwitchD-ospf-1-area-0.0.0.2] network 10.3.1.0 0.0.0.255
[SwitchD-ospf-1-area-0.0.0.2] network 10.5.1.0 0.0.0.255
[SwitchD-ospf-1-area-0.0.0.2] quit
[SwitchD-ospf-1] quit
Verifying the configuration
# Display information about neighbors on Switch A.
[SwitchA] display ospf peer verbose
OSPF Process 1 with Router ID 10.2.1.1
Neighbors
Area 0.0.0.0 interface 10.1.1.1(Vlan-interface100)'s neighbors
Router ID: 10.3.1.1 Address: 10.1.1.2 GR State: Normal
State: Full Mode: Nbr is master Priority: 1
DR: 10.1.1.1 BDR: 10.1.1.2 MTU: 0
Options is 0x02 (-|-|-|-|-|-|E|-)
Dead timer due in 37 sec
Neighbor is up for 06:03:59
Authentication Sequence: [ 0 ]
Neighbor state change count: 5
Area 0.0.0.1 interface 10.2.1.1(Vlan-interface200)'s neighbors
Router ID: 10.4.1.1 Address: 10.2.1.2 GR State: Normal
State: Full Mode: Nbr is master Priority: 1
DR: 10.2.1.1 BDR: 10.2.1.2 MTU: 0
Options is 0x02 (-|-|-|-|-|-|E|-)
Dead timer due in 32 sec
Neighbor is up for 06:03:12
Authentication Sequence: [ 0 ]
Neighbor state change count: 5
# Display OSPF routing information on Switch A.
[SwitchA] display ospf routing
OSPF Process 1 with Router ID 10.2.1.1
Routing Table
Routing for network
Destination Cost Type NextHop AdvRouter Area
10.2.1.0/24 1 Transit 10.2.1.1 10.2.1.1 0.0.0.1
10.3.1.0/24 2 Inter 10.1.1.2 10.3.1.1 0.0.0.0
10.4.1.0/24 2 Stub 10.2.1.2 10.4.1.1 0.0.0.1
10.5.1.0/24 3 Inter 10.1.1.2 10.3.1.1 0.0.0.0
10.1.1.0/24 1 Transit 10.1.1.1 10.2.1.1 0.0.0.0
Total nets: 5
Intra area: 3 Inter area: 2 ASE: 0 NSSA: 0
# Display OSPF routing information on Switch D.
[SwitchD] display ospf routing
OSPF Process 1 with Router ID 10.5.1.1
Routing Table
Routing for network
Destination Cost Type NextHop AdvRouter Area
10.2.1.0/24 3 Inter 10.3.1.1 10.3.1.1 0.0.0.2
10.3.1.0/24 1 Transit 10.3.1.2 10.3.1.1 0.0.0.2
10.4.1.0/24 4 Inter 10.3.1.1 10.3.1.1 0.0.0.2
10.5.1.0/24 1 Stub 10.5.1.1 10.5.1.1 0.0.0.2
10.1.1.0/24 2 Inter 10.3.1.1 10.3.1.1 0.0.0.2
Total nets: 5
Intra area: 2 Inter area: 3 ASE: 0 NSSA: 0
# On Switch D, ping the IP address 10.4.1.1 to test reachability.
[SwitchD] ping 10.4.1.1
Ping 10.4.1.1 (10.4.1.1): 56 data bytes, press CTRL_C to break
56 bytes from 10.4.1.1: icmp_seq=0 ttl=253 time=1.549 ms
56 bytes from 10.4.1.1: icmp_seq=1 ttl=253 time=1.539 ms
56 bytes from 10.4.1.1: icmp_seq=2 ttl=253 time=0.779 ms
56 bytes from 10.4.1.1: icmp_seq=3 ttl=253 time=1.702 ms
56 bytes from 10.4.1.1: icmp_seq=4 ttl=253 time=1.471 ms
--- Ping statistics for 10.4.1.1 ---
5 packet(s) transmitted, 5 packet(s) received, 0.0% packet loss
round-trip min/avg/max/std-dev = 0.779/1.408/1.702/0.323 ms
OSPF route redistribution configuration example
Network requirements
As shown in Figure 25:
· Enable OSPF on all the switches.
· Split the AS into three areas.
· Configure Switch A and Switch B as ABRs.
· Configure Switch C as an ASBR to redistribute external routes (static routes).
Configuration procedure
1. Configure IP addresses for interfaces. (Details not shown.)
3. Basic OSPF configuration example").
4. Configure OSPF to redistribute routes:
# On Switch C, configure a static route destined for network 3.1.2.0/24.
<SwitchC> system-view
[SwitchC] ip route-static 3.1.2.1 24 10.4.1.2
# On Switch C, configure OSPF to redistribute static routes.
[SwitchC] ospf 1
[SwitchC-ospf-1] import-route static
Verifying the configuration
# Display the ABR/ASBR information on Switch D.
<SwitchD> display ospf abr-asbr
OSPF Process 1 with Router ID 10.5.1.1
Routing Table to ABR and ASBR
Type Destination Area Cost Nexthop RtType
Intra 10.3.1.1 0.0.0.2 10 10.3.1.1 ABR
Inter 10.4.1.1 0.0.0.2 22 10.3.1.1 ASBR
# Display the OSPF routing table on Switch D.
<SwitchD> display ospf routing
OSPF Process 1 with Router ID 10.5.1.1
Routing Table
Routing for network
Destination Cost Type NextHop AdvRouter Area
10.2.1.0/24 22 Inter 10.3.1.1 10.3.1.1 0.0.0.2
10.3.1.0/24 10 Transit 10.3.1.2 10.3.1.1 0.0.0.2
10.4.1.0/24 25 Inter 10.3.1.1 10.3.1.1 0.0.0.2
10.5.1.0/24 10 Stub 10.5.1.1 10.5.1.1 0.0.0.2
10.1.1.0/24 12 Inter 10.3.1.1 10.3.1.1 0.0.0.2
Routing for ASEs
Destination Cost Type Tag NextHop AdvRouter
3.1.2.0/24 1 Type2 1 10.3.1.1 10.4.1.1
Total nets: 6
Intra area: 2 Inter area: 3 ASE: 1 NSSA: 0
OSPF route summarization configuration example
Network requirements
As shown in Figure 26:
· Configure OSPF on Switch A and Switch B in AS 200.
· Configure OSPF on Switch C, Switch D, and Switch E in AS 100.
· Configure an EBGP connection between Switch B and Switch C. Configure Switch B and Switch C to redistribute OSPF routes and direct routes into BGP and BGP routes into OSPF.
· Configure Switch B to advertise only summary route 10.0.0.0/8 to Switch A.
Configuration procedure
1. Configure IP addresses for interfaces. (Details not shown.)
2. Enable OSPF:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] router id 11.2.1.2
[SwitchA] ospf
[SwitchA-ospf-1] area 0
[SwitchA-ospf-1-area-0.0.0.0] network 11.2.1.0 0.0.0.255
[SwitchA-ospf-1-area-0.0.0.0] quit
[SwitchA-ospf-1] quit
# Configure Switch B.
<SwitchB> system-view
[SwitchB] router id 11.2.1.1
[SwitchB] ospf
[SwitchB-ospf-1] area 0
[SwitchB-ospf-1-area-0.0.0.0] network 11.2.1.0 0.0.0.255
[SwitchB-ospf-1-area-0.0.0.0] quit
[SwitchB-ospf-1] quit
# Configure Switch C.
<SwitchC> system-view
[SwitchC] router id 11.1.1.2
[SwitchC] ospf
[SwitchC-ospf-1] area 0
[SwitchC-ospf-1-area-0.0.0.0] network 10.1.1.0 0.0.0.255
[SwitchC-ospf-1-area-0.0.0.0] network 10.2.1.0 0.0.0.255
[SwitchC-ospf-1-area-0.0.0.0] quit
[SwitchC-ospf-1] quit
# Configure Switch D.
<SwitchD> system-view
[SwitchD] router id 10.3.1.1
[SwitchD] ospf
[SwitchD-ospf-1] area 0
[SwitchD-ospf-1-area-0.0.0.0] network 10.1.1.0 0.0.0.255
[SwitchD-ospf-1-area-0.0.0.0] network 10.3.1.0 0.0.0.255
[SwitchD-ospf-1-area-0.0.0.0] quit
[SwitchD-ospf-1] quit
# Configure Switch E.
<SwitchE> system-view
[SwitchE] router id 10.4.1.1
[SwitchE] ospf
[SwitchE-ospf-1] area 0
[SwitchE-ospf-1-area-0.0.0.0] network 10.2.1.0 0.0.0.255
[SwitchE-ospf-1-area-0.0.0.0] network 10.4.1.0 0.0.0.255
[SwitchE-ospf-1-area-0.0.0.0] quit
[SwitchE-ospf-1] quit
3. Configure BGP to redistribute OSPF routes and direct routes:
# Configure Switch B.
[SwitchB] bgp 200
[SwitchB-bgp] peer 11.1.1.2 as 100
[SwitchB-bgp] address-family ipv4 unicast
[SwitchB-bgp-ipv4] import-route ospf
[SwitchB-bgp-ipv4] import-route direct
[SwitchB-bgp ipv4] quit
[SwitchB-bgp] quit
# Configure Switch C.
[SwitchC] bgp 100
[SwitchC-bgp] peer 11.1.1.1 as 200
[SwitchC-bgp] address-family ipv4 unicast
[SwitchC-bgp-ipv4] import-route ospf
[SwitchC-bgp-ipv4]import-route direct
[SwitchC-bgp-ipv4] quit
[SwitchC-bgp] quit
4. Configure Switch B and Switch C to redistribute BGP routes into OSPF:
# Configure OSPF to redistribute routes from BGP on Switch B.
[SwitchB] ospf
[SwitchB-ospf-1] import-route bgp
# Configure OSPF to redistribute routes from BGP on Switch C.
[SwitchC] ospf
[SwitchC-ospf-1] import-route bgp
# Display the OSPF routing table on Switch A.
[SwitchA] display ip routing-table
Destinations : 16 Routes : 16
Destination/Mask Proto Pre Cost NextHop Interface
0.0.0.0/32 Direct 0 0 127.0.0.1 InLoop0
10.1.1.0/24 O_ASE2 150 1 11.2.1.1 Vlan100
10.2.1.0/24 O_ASE2 150 1 11.2.1.1 Vlan100
10.3.1.0/24 O_ASE2 150 1 11.2.1.1 Vlan100
10.4.1.0/24 O_ASE2 150 1 11.2.1.1 Vlan100
11.2.1.0/24 Direct 0 0 11.2.1.2 Vlan100
11.2.1.0/32 Direct 0 0 11.2.1.2 Vlan100
11.2.1.2/32 Direct 0 0 127.0.0.1 InLoop0
11.2.1.255/32 Direct 0 0 11.2.1.2 Vlan100
127.0.0.0/8 Direct 0 0 127.0.0.1 InLoop0
127.0.0.0/32 Direct 0 0 127.0.0.1 InLoop0
127.0.0.1/32 Direct 0 0 127.0.0.1 InLoop0
127.255.255.255/32 Direct 0 0 127.0.0.1 InLoop0
224.0.0.0/4 Direct 0 0 0.0.0.0 NULL0
224.0.0.0/24 Direct 0 0 0.0.0.0 NULL0
255.255.255.255/32 Direct 0 0 127.0.0.1 InLoop0
5. Configure route summarization:
# Configure route summarization on Switch B to advertise a summary route 10.0.0.0/8.
[SwitchB-ospf-1] asbr-summary 10.0.0.0 8
# Display the IP routing table on Switch A.
[SwitchA] display ip routing-table
Destinations : 13 Routes : 13
Destination/Mask Proto Pre Cost NextHop Interface
0.0.0.0/32 Direct 0 0 127.0.0.1 InLoop0
10.0.0.0/8 O_ASE2 150 2 11.2.1.1 Vlan100
11.2.1.0/24 Direct 0 0 11.2.1.2 Vlan100
11.2.1.0/32 Direct 0 0 11.2.1.2 Vlan100
11.2.1.2/32 Direct 0 0 127.0.0.1 InLoop0
11.2.1.255/32 Direct 0 0 11.2.1.2 Vlan100
127.0.0.0/8 Direct 0 0 127.0.0.1 InLoop0
127.0.0.0/32 Direct 0 0 127.0.0.1 InLoop0
127.0.0.1/32 Direct 0 0 127.0.0.1 InLoop0
127.255.255.255/32 Direct 0 0 127.0.0.1 InLoop0
224.0.0.0/4 Direct 0 0 0.0.0.0 NULL0
224.0.0.0/24 Direct 0 0 0.0.0.0 NULL0
255.255.255.255/32 Direct 0 0 127.0.0.1 InLoop0
The output shows that routes 10.1.1.0/24, 10.2.1.0/24, 10.3.1.0/24 and 10.4.1.0/24 are summarized into a single route 10.0.0.0/8.
OSPF stub area configuration example
Network requirements
As shown in Figure 27:
· Enable OSPF on all switches, and split the AS into three areas.
· Configure Switch A and Switch B as ABRs to forward routing information between areas.
· Configure Switch D as the ASBR to redistribute static routes.
· Configure Area 1 as a stub area to reduce advertised LSAs without influencing reachability.
Configuration procedure
1. Configure IP addresses for interfaces. (Details not shown.)
3. Basic OSPF configuration example").
4. Configure route redistribution:
# Configure Switch D to redistribute static routes.
<SwitchD> system-view
[SwitchD] ip route-static 3.1.2.1 24 10.5.1.2
[SwitchD] ospf
[SwitchD-ospf-1] import-route static
[SwitchD-ospf-1] quit
# Display ABR/ASBR information on Switch C.
<SwitchC> display ospf abr-asbr
OSPF Process 1 with Router ID 10.4.1.1
Routing Table to ABR and ASBR
Type Destination Area Cost Nexthop RtType
Intra 10.2.1.1 0.0.0.1 3 10.2.1.1 ABR
Inter 10.5.1.1 0.0.0.1 7 10.2.1.1 ASBR
# Display OSPF routing table on Switch C.
<SwitchC> display ospf routing
OSPF Process 1 with Router ID 10.4.1.1
Routing Table
Routing for network
Destination Cost Type NextHop AdvRouter Area
10.2.1.0/24 3 Transit 0.0.0.0 10.2.1.1 0.0.0.1
10.3.1.0/24 7 Inter 10.2.1.1 10.2.1.1 0.0.0.1
10.4.1.0/24 3 Stub 10.4.1.1 10.4.1.1 0.0.0.1
10.5.1.0/24 17 Inter 10.2.1.1 10.2.1.1 0.0.0.1
10.1.1.0/24 5 Inter 10.2.1.1 10.2.1.1 0.0.0.1
Routing for ASEs
Destination Cost Type Tag NextHop AdvRouter
3.1.2.0/24 1 Type2 1 10.2.1.1 10.5.1.1
Total nets: 6
Intra area: 2 Inter area: 3 ASE: 1 NSSA: 0
The output shows that Switch C's routing table contains an AS external route.
5. Configure Area 1 as a stub area:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] ospf
[SwitchA-ospf-1] area 1
[SwitchA-ospf-1-area-0.0.0.1] stub
[SwitchA-ospf-1-area-0.0.0.1] quit
[SwitchA-ospf-1] quit
# Configure Switch C.
<SwitchC> system-view
[SwitchC] ospf
[SwitchC-ospf-1] area 1
[SwitchC-ospf-1-area-0.0.0.1] stub
[SwitchC-ospf-1-area-0.0.0.1] quit
[SwitchC-ospf-1] quit
# Display OSPF routing information on Switch C
[SwitchC] display ospf routing
OSPF Process 1 with Router ID 10.4.1.1
Routing Table
Routing for network
Destination Cost Type NextHop AdvRouter Area
0.0.0.0/0 4 Inter 10.2.1.1 10.2.1.1 0.0.0.1
10.2.1.0/24 3 Transit 0.0.0.0 10.2.1.1 0.0.0.1
10.3.1.0/24 7 Inter 10.2.1.1 10.2.1.1 0.0.0.1
10.4.1.0/24 3 Stub 10.4.1.1 10.4.1.1 0.0.0.1
10.5.1.0/24 17 Inter 10.2.1.1 10.2.1.1 0.0.0.1
10.1.1.0/24 5 Inter 10.2.1.1 10.2.1.1 0.0.0.1
Total nets: 6
Intra area: 2 Inter area: 4 ASE: 0 NSSA: 0
The output shows that a default route replaces the AS external route.
# Configure Area 1 as a totally stub area.
[SwitchA] ospf
[SwitchA-ospf-1] area 1
[SwitchA-ospf-1-area-0.0.0.1] stub no-summary
[SwitchA-ospf-1-area-0.0.0.1] quit
[SwitchA-ospf-1] quit
# Display OSPF routing information on Switch C.
[SwitchC] display ospf routing
OSPF Process 1 with Router ID 10.4.1.1
Routing Table
Routing for network
Destination Cost Type NextHop AdvRouter Area
0.0.0.0/0 4 Inter 10.2.1.1 10.2.1.1 0.0.0.1
10.2.1.0/24 3 Transit 0.0.0.0 10.4.1.1 0.0.0.1
10.4.1.0/24 3 Stub 10.4.1.1 10.4.1.1 0.0.0.1
Total nets: 3
Intra area: 2 Inter area: 1 ASE: 0 NSSA: 0
The output shows that inter-area routes are removed, and only one external route (a default route) exists on Switch C.
OSPF NSSA area configuration example
Network requirements
As shown in Figure 28:
· Configure OSPF on all switches and split AS into three areas.
· Configure Switch A and Switch B as ABRs to forward routing information between areas.
· Configure Area 1 as an NSSA area and configure Switch C as an ASBR to redistribute static routes into the AS.
Configuration procedure
1. Configure IP addresses for interfaces.
3. Basic OSPF configuration example").
4. Configure Area 1 as an NSSA area:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] ospf
[SwitchA-ospf-1] area 1
[SwitchA-ospf-1-area-0.0.0.1] nssa
[SwitchA-ospf-1-area-0.0.0.1] quit
[SwitchA-ospf-1] quit
# Configure Switch C.
<SwitchC> system-view
[SwitchC] ospf
[SwitchC-ospf-1] area 1
[SwitchC-ospf-1-area-0.0.0.1] nssa
[SwitchC-ospf-1-area-0.0.0.1] quit
[SwitchC-ospf-1] quit
# Display OSPF routing information on Switch C.
[SwitchC] display ospf routing
OSPF Process 1 with Router ID 10.4.1.1
Routing Table
Routing for network
Destination Cost Type NextHop AdvRouter Area
10.2.1.0/24 3 Transit 10.2.1.2 10.4.1.1 0.0.0.1
10.3.1.0/24 7 Inter 10.2.1.1 10.2.1.1 0.0.0.1
10.4.1.0/24 3 Stub 10.4.1.1 10.4.1.1 0.0.0.1
10.5.1.0/24 17 Inter 10.2.1.1 10.2.1.1 0.0.0.1
10.1.1.0/24 5 Inter 10.2.1.1 10.2.1.1 0.0.0.1
Total nets: 5
Intra area: 2 Inter area: 3 ASE: 0 NSSA: 0
5. Configure route redistribution:
# Configure Switch C to redistribute static routes.
[SwitchC] ip route-static 3.1.3.1 24 10.4.1.2
[SwitchC] ospf
[SwitchC-ospf-1] import-route static
[SwitchC-ospf-1] quit
# Display OSPF routing information on Switch D.
<SwitchD> display ospf routing
OSPF Process 1 with Router ID 10.5.1.1
Routing Table
Routing for network
Destination Cost Type NextHop AdvRouter Area
10.2.1.0/24 22 Inter 10.3.1.1 10.3.1.1 0.0.0.2
10.3.1.0/24 10 Transit 10.3.1.2 10.3.1.1 0.0.0.2
10.4.1.0/24 25 Inter 10.3.1.1 10.3.1.1 0.0.0.2
10.5.1.0/24 10 Stub 10.5.1.1 10.5.1.1 0.0.0.2
10.1.1.0/24 12 Inter 10.3.1.1 10.3.1.1 0.0.0.2
Routing for ASEs
Destination Cost Type Tag NextHop AdvRouter
3.1.3.0/24 1 Type2 1 10.3.1.1 10.2.1.1
Total nets: 6
Intra area: 2 Inter area: 3 ASE: 1 NSSA: 0
The output shows that an external route imported from the NSSA area exists on Switch D.
OSPF DR election configuration example
Network requirements
As shown in Figure 29:
· Enable OSPF on Switches A, B, C, and D on the same network.
· Configure Switch A as the DR, and configure Switch C as the BDR.
Configuration procedure
1. Configure IP addresses for interfaces. (Details not shown.)
2. Enable OSPF:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] router id 1.1.1.1
[SwitchA] ospf
[SwitchA-ospf-1] area 0
[SwitchA-ospf-1-area-0.0.0.0] network 192.168.1.0 0.0.0.255
[SwitchA-ospf-1-area-0.0.0.0] quit
[SwitchA-ospf-1] quit
# Configure Switch B.
<SwitchB> system-view
[SwitchB] router id 2.2.2.2
[SwitchB] ospf
[SwitchB-ospf-1] area 0
[SwitchB-ospf-1-area-0.0.0.0] network 192.168.1.0 0.0.0.255
[SwitchB-ospf-1-area-0.0.0.0] quit
[SwitchB-ospf-1] quit
# Configure Switch C.
<SwitchC> system-view
[SwitchC] router id 3.3.3.3
[SwitchC] ospf
[SwitchC-ospf-1] area 0
[SwitchC-ospf-1-area-0.0.0.0] network 192.168.1.0 0.0.0.255
[SwitchC-ospf-1-area-0.0.0.0] quit
[SwitchC-ospf-1] quit
# Configure Switch D.
<SwitchD> system-view
[SwitchD] router id 4.4.4.4
[SwitchD] ospf
[SwitchD-ospf-1] area 0
[SwitchD-ospf-1-area-0.0.0.0] network 192.168.1.0 0.0.0.255
[SwitchD-ospf-1-area-0.0.0.0] quit
[SwitchD-ospf-1] quit
# Display OSPF neighbor information on Switch A.
[SwitchA] display ospf peer verbose
OSPF Process 1 with Router ID 1.1.1.1
Neighbors
Area 0.0.0.0 interface 192.168.1.1(Vlan-interface1)'s neighbors
Router ID: 2.2.2.2 Address: 192.168.1.2 GR State: Normal
State: 2-Way Mode: None Priority: 1
DR: 192.168.1.4 BDR: 192.168.1.3 MTU: 0
Options is 0x02 (-|-|-|-|-|-|E|-)
Dead timer due in 38 sec
Neighbor is up for 00:01:31
Authentication Sequence: [ 0 ]
Neighbor state change count: 6
BFD status: Disabled
Router ID: 3.3.3.3 Address: 192.168.1.3 GR State: Normal
State: Full Mode: Nbr is master Priority: 1
DR: 192.168.1.4 BDR: 192.168.1.3 MTU: 0
Options is 0x02 (-|-|-|-|-|-|E|-)
Dead timer due in 31 sec
Neighbor is up for 00:01:28
Authentication Sequence: [ 0 ]
Neighbor state change count: 6
BFD status: Disabled
Router ID: 4.4.4.4 Address: 192.168.1.4 GR State: Normal
State: Full Mode: Nbr is master Priority: 1
DR: 192.168.1.4 BDR: 192.168.1.3 MTU: 0
Options is 0x02 (-|-|-|-|-|-|E|-)
Dead timer due in 31 sec
Neighbor is up for 00:01:28
Authentication Sequence: [ 0 ]
Neighbor state change count: 6
BFD status: Disabled
The output shows that Switch D is the DR and Switch C is the BDR.
3. Configure router priorities on interfaces:
# Configure Switch A.
[SwitchA] interface vlan-interface 1
[SwitchA-Vlan-interface1] ospf dr-priority 100
[SwitchA-Vlan-interface1] quit
# Configure Switch B.
[SwitchB] interface vlan-interface 1
[SwitchB-Vlan-interface1] ospf dr-priority 0
[SwitchB-Vlan-interface1] quit
# Configure Switch C.
[SwitchC] interface vlan-interface 1
[SwitchC-Vlan-interface1] ospf dr-priority 2
[SwitchC-Vlan-interface1] quit
# Display neighbor information on Switch D.
<SwitchD> display ospf peer verbose
OSPF Process 1 with Router ID 4.4.4.4
Neighbors
Area 0.0.0.0 interface 192.168.1.4(Vlan-interface1)'s neighbors
Router ID: 1.1.1.1 Address: 192.168.1.1 GR State: Normal
State: Full Mode:Nbr is slave Priority: 100
DR: 192.168.1.4 BDR: 192.168.1.3 MTU: 0
Options is 0x02 (-|-|-|-|-|-|E|-)
Dead timer due in 31 sec
Neighbor is up for 00:11:17
Authentication Sequence: [ 0 ]
Neighbor state change count: 6
BFD status: Disabled
Router ID: 2.2.2.2 Address: 192.168.1.2 GR State: Normal
State: Full Mode:Nbr is slave Priority: 0
DR: 192.168.1.4 BDR: 192.168.1.3 MTU: 0
Options is 0x02 (-|-|-|-|-|-|E|-)
Dead timer due in 35 sec
Neighbor is up for 00:11:19
Authentication Sequence: [ 0 ]
Neighbor state change count: 6
BFD status: Disabled
Router ID: 3.3.3.3 Address: 192.168.1.3 GR State: Normal
State: Full Mode:Nbr is slave Priority: 2
DR: 192.168.1.4 BDR: 192.168.1.3 MTU: 0
Options is 0x02 (-|-|-|-|-|-|E|-)
Dead timer due in 33 sec
Neighbor is up for 00:11:15
Authentication Sequence: [ 0 ]
Neighbor state change count: 6
BFD status: Disabled
The output shows that the DR and BDR are not changed, because the priority settings do not take effect immediately.
4. Restart OSPF process:
# Restart the OSPF process of Switch D.
<SwitchD> reset ospf 1 process
Warning : Reset OSPF process? [Y/N]:y
# Display neighbor information on Switch D.
<SwitchD> display ospf peer verbose
OSPF Process 1 with Router ID 4.4.4.4
Neighbors
Area 0.0.0.0 interface 192.168.1.4(Vlan-interface1)'s neighbors
Router ID: 1.1.1.1 Address: 192.168.1.1 GR State: Normal
State: Full Mode: Nbr is slave Priority: 100
DR: 192.168.1.1 BDR: 192.168.1.3 MTU: 0
Options is 0x02 (-|-|-|-|-|-|E|-)
Dead timer due in 39 sec
Neighbor is up for 00:01:40
Authentication Sequence: [ 0 ]
Neighbor state change count: 6
BFD status: Disabled
Router ID: 2.2.2.2 Address: 192.168.1.2 GR State: Normal
State: 2-Way Mode: None Priority: 0
DR: 192.168.1.1 BDR: 192.168.1.3 MTU: 0
Options is 0x02 (-|-|-|-|-|-|E|-)
Dead timer due in 35 sec
Neighbor is up for 00:01:44
Authentication Sequence: [ 0 ]
Neighbor state change count: 6
BFD status: Disabled
Router ID: 3.3.3.3 Address: 192.168.1.3 GR State: Normal
State: Full Mode: Nbr is slave Priority: 2
DR: 192.168.1.1 BDR: 192.168.1.3 MTU: 0
Options is 0x02 (-|-|-|-|-|-|E|-)
Dead timer due in 39 sec
Neighbor is up for 00:01:41
Authentication Sequence: [ 0 ]
Neighbor state change count: 6
BFD status: Disabled
The output shows that Switch A becomes the DR and Switch C becomes the BDR.
If the neighbor state is full, Switch D has established an adjacency with the neighbor. If the neighbor state is 2-way, the two switches are not the DR or the BDR, and they do not exchange LSAs.
# Display OSPF interface information.
[SwitchA] display ospf interface
OSPF Process 1 with Router ID 1.1.1.1
Interfaces
Area: 0.0.0.0
IP Address Type State Cost Pri DR BDR
192.168.1.1 Broadcast DR 1 100 192.168.1.1 192.168.1.3
[SwitchB] display ospf interface
OSPF Process 1 with Router ID 2.2.2.2
Interfaces
Area: 0.0.0.0
IP Address Type State Cost Pri DR BDR
192.168.1.2 Broadcast DROther 1 0 192.168.1.1 192.168.1.3
The interface state DROther means the interface is not the DR or BDR.
OSPF virtual link configuration example
Network requirements
As shown in Figure 30, configure a virtual link between Switch B and Switch C to connect Area 2 to the backbone area. After configuration, Switch B can learn routes to Area 2.
Configuration procedure
1. Configure IP addresses for interfaces. (Details not shown.)
2. Enable OSPF:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] ospf 1 router-id 1.1.1.1
[SwitchA-ospf-1] area 0
[SwitchA-ospf-1-area-0.0.0.0] network 10.1.1.0 0.0.0.255
[SwitchA-ospf-1-area-0.0.0.0] quit
[SwitchA-ospf-1] quit
# Configure Switch B.
<SwitchB> system-view
[SwitchB] ospf 1 router-id 2.2.2.2
[SwitchB-ospf-1] area 0
[SwitchB-ospf-1-area-0.0.0.0] network 10.1.1.0 0.0.0.255
[SwitchB-ospf-1-area-0.0.0.0] quit
[SwitchB-ospf-1] area 1
[SwitchB–ospf-1-area-0.0.0.1] network 10.2.1.0 0.0.0.255
[SwitchB–ospf-1-area-0.0.0.1] quit
[SwitchB-ospf-1] quit
# Configure Switch C.
<SwitchC> system-view
[SwitchC] ospf 1 router-id 3.3.3.3
[SwitchC-ospf-1] area 1
[SwitchC-ospf-1-area-0.0.0.1] network 10.2.1.0 0.0.0.255
[SwitchC-ospf-1-area-0.0.0.1] quit
[SwitchC-ospf-1] area 2
[SwitchC–ospf-1-area-0.0.0.2] network 10.3.1.0 0.0.0.255
[SwitchC–ospf-1-area-0.0.0.2] quit
[SwitchC-ospf-1] quit
# Configure Switch D.
<SwitchD> system-view
[SwitchD] ospf 1 router-id 4.4.4.4
[SwitchD-ospf-1] area 2
[SwitchD-ospf-1-area-0.0.0.2] network 10.3.1.0 0.0.0.255
[SwitchD-ospf-1-area-0.0.0.2] quit
[SwitchD-ospf-1] quit
# Display the OSPF routing table on Switch B.
[SwitchB] display ospf routing
OSPF Process 1 with Router ID 2.2.2.2
Routing Table
Routing for network
Destination Cost Type NextHop AdvRouter Area
10.2.1.0/24 2 Transit 10.2.1.1 3.3.3.3 0.0.0.1
10.1.1.0/24 2 Transit 10.1.1.2 2.2.2.2 0.0.0.0
Total nets: 2
Intra area: 2 Inter area: 0 ASE: 0 NSSA: 0
The output shows that Switch B does not have routes to Area 2 because Area 0 is not directly connected to Area 2.
3. Configure a virtual link:
# Configure Switch B.
[SwitchB] ospf
[SwitchB-ospf-1] area 1
[SwitchB-ospf-1-area-0.0.0.1] vlink-peer 3.3.3.3
[SwitchB-ospf-1-area-0.0.0.1] quit
[SwitchB-ospf-1] quit
# Configure Switch C.
[SwitchC] ospf 1
[SwitchC-ospf-1] area 1
[SwitchC-ospf-1-area-0.0.0.1] vlink-peer 2.2.2.2
[SwitchC-ospf-1-area-0.0.0.1] quit
[SwitchC-ospf-1] quit
# Display the OSPF routing table on Switch B.
[SwitchB] display ospf routing
OSPF Process 1 with Router ID 2.2.2.2
Routing Table
Routing for network
Destination Cost Type NextHop AdvRouter Area
10.2.1.0/24 2 Transit 10.2.1.1 3.3.3.3 0.0.0.1
10.3.1.0/24 5 Inter 10.2.1.2 3.3.3.3 0.0.0.0
10.1.1.0/24 2 Transit 10.1.1.2 2.2.2.2 0.0.0.0
Total nets: 3
Intra area: 2 Inter area: 1 ASE: 0 NSSA: 0
The output shows that Switch B has learned the route 10.3.1.0/24 to Area 2.
OSPF GR configuration example
Network requirements
As shown in Figure 31:
· Switch A, Switch B, and Switch C that belong to the same AS and the same OSPF routing domain are GR capable.
· Switch A acts as the non-IETF GR restarter. Switch B and Switch C are the GR helpers, and synchronize their LSDBs with Switch A through OOB communication of GR.
Configuration procedure
1. Configure IP addresses for interfaces. (Details not shown.)
2. Enable OSPF:
# Configure Switch A.
SwitchA> system-view
[SwitchA] router id 1.1.1.1
[SwitchA] ospf 100
[SwitchA-ospf-100] area 0
[SwitchA-ospf-100-area-0.0.0.0] network 192.1.1.0 0.0.0.255
[SwitchA-ospf-100-area-0.0.0.0] quit
[SwitchA-ospf-1] quit
# Configure Switch B.
<SwitchB> system-view
[SwitchB] router id 2.2.2.2
[SwitchB] ospf 100
[SwitchB-ospf-100] area 0
[SwitchB-ospf-100-area-0.0.0.0] network 192.1.1.0 0.0.0.255
[SwitchB-ospf-100-area-0.0.0.0] quit
[SwitchB-ospf-1] quit
# Configure Switch C.
<SwitchC> system-view
[SwitchC] router id 3.3.3.3
[SwitchC] ospf 100
[SwitchC-ospf-100] area 0
[SwitchC-ospf-100-area-0.0.0.0] network 192.1.1.0 0.0.0.255
[SwitchC-ospf-100-area-0.0.0.0] quit
[SwitchC-ospf-1] quit
3. Configure OSPF GR:
# Configure Switch A as the non-IETF OSPF GR restarter: enable the link-local signaling capability, the out-of-band re-synchronization capability, and non-IETF GR capability for OSPF process 100.
[SwitchA-ospf-100] enable link-local-signaling
[SwitchA-ospf-100] enable out-of-band-resynchronization
[SwitchA-ospf-100] graceful-restart
[SwitchA-ospf-100] quit
# Configure Switch B as the GR helper: enable the link-local signaling capability and the out-of-band re-synchronization capability for OSPF process 100.
[SwitchB-ospf-100] enable link-local-signaling
[SwitchB-ospf-100] enable out-of-band-resynchronization
# Configure Switch C as the GR helper: enable the link-local signaling capability and the out-of-band re-synchronization capability for OSPF process 100.
[SwitchC-ospf-100] enable link-local-signaling
[SwitchC-ospf-100] enable out-of-band-resynchronization
Verifying the configuration
# Enable OSPF GR event debugging and restart the OSPF process by using GR on Switch A.
<SwitchA> debugging ospf event graceful-restart
<SwitchA> terminal monitor
<SwitchA> terminal logging level 7
<SwitchA> reset ospf 100 process graceful-restart
Reset OSPF process? [Y/N]:y
%Oct 21 15:29:28:727 2011 SwitchA OSPF/5/OSPF_NBR_CHG: OSPF 100 Neighbor 192.1.1.2(Vlan-interface100) from Full to Down.
%Oct 21 15:29:28:729 2011 SwitchA OSPF/5/OSPF_NBR_CHG: OSPF 100 Neighbor 192.1.1.3(Vlan-interface100) from Full to Down.
*Oct 21 15:29:28:735 2011 SwitchA OSPF/7/DEBUG:
OSPF 100 nonstandard GR Started for OSPF Router
*Oct 21 15:29:28:735 2011 SwitchA OSPF/7/DEBUG:
OSPF 100 created GR wait timer,timeout interval is 40(s).
*Oct 21 15:29:28:735 2011 SwitchA OSPF/7/DEBUG:
OSPF 100 created GR Interval timer,timeout interval is 120(s).
*Oct 21 15:29:28:758 2011 SwitchA OSPF/7/DEBUG:
OSPF 100 created OOB Progress timer for neighbor 192.1.1.3.
*Oct 21 15:29:28:766 2011 SwitchA OSPF/7/DEBUG:
OSPF 100 created OOB Progress timer for neighbor 192.1.1.2.
%Oct 21 15:29:29:902 2011 SwitchA OSPF/5/OSPF_NBR_CHG: OSPF 100 Neighbor 192.1.1.2(Vlan-interface100) from Loading to Full.
*Oct 21 15:29:29:902 2011 SwitchA OSPF/7/DEBUG:
OSPF 100 deleted OOB Progress timer for neighbor 192.1.1.2.
%Oct 21 15:29:30:897 2011 SwitchA OSPF/5/OSPF_NBR_CHG: OSPF 100 Neighbor 192.1.1.3(Vlan-interface100) from Loading to Full.
*Oct 21 15:29:30:897 2011 SwitchA OSPF/7/DEBUG:
OSPF 100 deleted OOB Progress timer for neighbor 192.1.1.3.
*Oct 21 15:29:30:911 2011 SwitchA OSPF/7/DEBUG:
OSPF GR: Process 100 Exit Restart,Reason : DR or BDR change,for neighbor : 192.1.1.3.
*Oct 21 15:29:30:911 2011 SwitchA OSPF/7/DEBUG:
OSPF 100 deleted GR Interval timer.
*Oct 21 15:29:30:912 2011 SwitchA OSPF/7/DEBUG:
OSPF 100 deleted GR wait timer.
%Oct 21 15:29:30:920 2011 SwitchA OSPF/5/OSPF_NBR_CHG: OSPF 100 Neighbor 192.1.1.2(Vlan-interface100) from Full to Down.
%Oct 21 15:29:30:921 2011 SwitchA OSPF/5/OSPF_NBR_CHG: OSPF 100 Neighbor 192.1.1.3(Vlan-interface100) from Full to Down.
%Oct 21 15:29:33:815 2011 SwitchA OSPF/5/OSPF_NBR_CHG: OSPF 100 Neighbor 192.1.1.3(Vlan-interface100) from Loading to Full.
%Oct 21 15:29:35:578 2011 SwitchA OSPF/5/OSPF_NBR_CHG: OSPF 100 Neighbor 192.1.1.2(Vlan-interface100) from Loading to Full.
The output shows that Switch A completes GR.
OSPF NSR configuration example
Network requirements
As shown in Figure 32, Switch S, Switch A, and Switch B belong to the same OSPF routing domain. Enable OSPF NSR on Switch S to ensure correct routing when an active/standby switchover occurs on Switch S.
Configuration procedure
1. Configure IP addresses and subnet masks for interfaces on the switches. (Details not shown.)
2. Configure OSPF on the switches to ensure the following: (Details not shown.)
? Switch S, Switch A, and Switch B can communicate with each other at Layer 3.
? Dynamic route update can be implemented among them with OSPF.
3. Enable OSPF NSR on Switch S.
<SwitchS> system-view
[SwitchS] ospf 100
[SwitchS-ospf-100] non-stop-routing
[SwitchS-ospf-100] quit
Verifying the configuration
# Perform an active/standby switchover on Switch S.
[SwitchS] placement reoptimize
Predicted changes to the placement
Program Current location New location
---------------------------------------------------------------------
lb 0/0 0/0
lsm 0/0 0/0
slsp 0/0 0/0
rib6 0/0 0/0
routepolicy 0/0 0/0
rib 0/0 0/0
staticroute6 0/0 0/0
staticroute 0/0 0/0
ospf 0/0 1/0
Continue? [y/n]:y
Re-optimization of the placement start. You will be notified on completion
Re-optimization of the placement complete. Use 'display placement' to view the new placement
# During the switchover period, display OSPF neighbors on Switch A to verify the neighbor relationship between Switch A and Switch S.
<SwitchA> display ospf peer
OSPF Process 1 with Router ID 2.2.2.1
Neighbor Brief Information
Area: 0.0.0.0
Router ID Address Pri Dead-Time State Interface
3.3.3.1 12.12.12.2 1 37 Full/BDR Vlan100
# Display OSPF routes on Switch A to verify if Switch A has a route to the loopback interface on Switch B.
<SwitchA> display ospf routing
OSPF Process 1 with Router ID 2.2.2.1
Routing Table
Routing for network
Destination Cost Type NextHop AdvRouter Area
44.44.44.44/32 2 Stub 12.12.12.2 4.4.4.1 0.0.0.0
14.14.14.0/24 2 Transit 12.12.12.2 4.4.4.1 0.0.0.0
22.22.22.22/32 0 Stub 22.22.22.22 2.2.2.1 0.0.0.0
12.12.12.0/24 1 Transit 12.12.12.1 2.2.2.1 0.0.0.0
Total nets: 4
Intra area: 4 Inter area: 0 ASE: 0 NSSA: 0
# Display OSPF neighbors on Switch B to verify the neighbor relationship between Switch B and Switch S.
<SwitchB> display ospf peer
OSPF Process 1 with Router ID 4.4.4.1
Neighbor Brief Information
Area: 0.0.0.0
Router ID Address Pri Dead-Time State Interface
3.3.3.1 14.14.14.2 1 39 Full/BDR Vlan200
# Display OSPF routes on Switch B to verify if Switch B has a route to the loopback interface on Switch A.
<SwitchB> display ospf routing
OSPF Process 1 with Router ID 4.4.4.1
Routing Table
Routing for network
Destination Cost Type NextHop AdvRouter Area
44.44.44.44/32 0 Stub 44.44.44.44 4.4.4.1 0.0.0.0
14.14.14.0/24 1 Transit 14.14.14.1 4.4.4.1 0.0.0.0
22.22.22.22/32 2 Stub 14.14.14.2 2.2.2.1 0.0.0.0
12.12.12.0/24 2 Transit 14.14.14.2 2.2.2.1 0.0.0.0
Total nets: 4
Intra area: 4 Inter area: 0 ASE: 0 NSSA: 0
The output shows the following when an active/standby switchover occurs on Switch S:
· The neighbor relationships and routing information on Switch A and Switch B have not changed.
· The traffic from Switch A to Switch B has not been impacted.
BFD for OSPF configuration example
Network requirements
As shown in Figure 33, run OSPF on Switch A, Switch B, and Switch C so that they are reachable to each other at the network layer.
· When the link over which Switch A and Switch B communicate through a Layer 2 switch fails, BFD can quickly detect the failure and notify OSPF of the failure.
· Switch A and Switch B then communicate through Switch C.
Table 9 Interface and IP address assignment
Device |
Interface |
IP address |
Switch A |
Vlan-int10 |
192.168.0.102/24 |
Switch A |
Vlan-int11 |
10.1.1.102/24 |
Switch A |
Loop0 |
121.1.1.1/32 |
Switch B |
Vlan-int10 |
192.168.0.100/24 |
Switch B |
Vlan-int13 |
13.1.1.1/24 |
Switch B |
Loop0 |
120.1.1.1/32 |
Switch C |
Vlan-int11 |
10.1.1.100/24 |
Switch C |
Vlan-int13 |
13.1.1.2/24 |
Configuration procedure
1. Configure IP addresses for interfaces. (Details not shown.)
2. Enable OSPF:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] ospf
[SwitchA-ospf-1] area 0
[SwitchA-ospf-1-area-0.0.0.0] network 192.168.0.0 0.0.0.255
[SwitchA-ospf-1-area-0.0.0.0] network 10.1.1.0 0.0.0.255
[SwitchA-ospf-1-area-0.0.0.0] network 121.1.1.1 0.0.0.0
[SwitchA-ospf-1-area-0.0.0.0] quit
[SwitchA-ospf-1] quit
# Configure Switch B.
<SwitchB> system-view
[SwitchB] ospf
[SwitchB-ospf-1] area 0
[SwitchB-ospf-1-area-0.0.0.0] network 192.168.0.0 0.0.0.255
[SwitchB-ospf-1-area-0.0.0.0] network 13.1.1.0 0.0.0.255
[SwitchB-ospf-1-area-0.0.0.0] network 120.1.1.1 0.0.0.0
[SwitchB-ospf-1-area-0.0.0.0] quit
[SwitchB-ospf-1] quit
# Configure Switch C.
<SwitchC> system-view
[SwitchC] ospf
[SwitchC-ospf-1] area 0
[SwitchC-ospf-1-area-0.0.0.0] network 10.1.1.0 0.0.0.255
[SwitchC-ospf-1-area-0.0.0.0] network 13.1.1.0 0.0.0.255
[SwitchC-ospf-1-area-0.0.0.0] quit
[SwitchC-ospf-1] quit
3. Configure BFD:
# Enable BFD on Switch A and configure BFD parameters.
[SwitchA] bfd session init-mode active
[SwitchA] interface vlan-interface 10
[SwitchA-Vlan-interface10] ospf bfd enable
[SwitchA-Vlan-interface10] bfd min-transmit-interval 500
[SwitchA-Vlan-interface10] bfd min-receive-interval 500
[SwitchA-Vlan-interface10] bfd detect-multiplier 7
[SwitchA-Vlan-interface10] quit
# Enable BFD on Switch B and configure BFD parameters.
[SwitchB] bfd session init-mode active
[SwitchB] interface vlan-interface 10
[SwitchB-Vlan-interface10] ospf bfd enable
[SwitchB-Vlan-interface10] bfd min-transmit-interval 500
[SwitchB-Vlan-interface10] bfd min-receive-interval 500
[SwitchB-Vlan-interface10] bfd detect-multiplier 6
[SwitchB-Vlan-interface10] quit
Verifying the configuration
# Display the BFD information on Switch A.
<SwitchA> display bfd session
Total Session Num: 1 Up Session Num: 1 Init Mode: Active
IPv4 Session Working Under Ctrl Mode:
LD/RD SourceAddr DestAddr State Holdtime Interface
3/1 192.168.0.102 192.168.0.100 Up 1700ms Vlan10
# Display routes destined for 120.1.1.1/32 on Switch A.
<SwitchA> display ip routing-table 120.1.1.1 verbose
Summary Count : 1
Destination: 120.1.1.1/32
Protocol: O_INTRA
Process ID: 1
SubProtID: 0x1 Age: 04h20m37s
Cost: 1 Preference: 10
IpPre: N/A QosLocalID: N/A
Tag: 0 State: Active Adv
OrigTblID: 0x0 OrigVrf: default-vrf
TableID: 0x2 OrigAs: 0
NibID: 0x26000002 LastAs: 0
AttrID: 0xffffffff Neighbor: 0.0.0.0
Flags: 0x1008c OrigNextHop: 192.168.0.100
Label: NULL RealNextHop: 192.168.0.100
BkLabel: NULL BkNextHop: N/A
Tunnel ID: Invalid Interface: Vlan-interface10
BkTunnel ID: Invalid BkInterface: N/A
FtnIndex: 0x0 TrafficIndex: N/A
Connector: N/A
The output shows that Switch A communicates with Switch B through VLAN-interface 10. Then the link over VLAN-interface 10 fails.
# Display routes destined for 120.1.1.1/32 on Switch A.
<SwitchA> display ip routing-table 120.1.1.1 verbose
Summary Count : 1
Destination: 120.1.1.1/32
Protocol: O_INTRA
Process ID: 1
SubProtID: 0x1 Age: 04h20m37s
Cost: 2 Preference: 10
IpPre: N/A QosLocalID: N/A
Tag: 0 State: Active Adv
OrigTblID: 0x0 OrigVrf: default-vrf
TableID: 0x2 OrigAs: 0
NibID: 0x26000002 LastAs: 0
AttrID: 0xffffffff Neighbor: 0.0.0.0
Flags: 0x1008c OrigNextHop: 10.1.1.100
Label: NULL RealNextHop: 10.1.1.100
BkLabel: NULL BkNextHop: N/A
Tunnel ID: Invalid Interface: Vlan-interface11
BkTunnel ID: Invalid BkInterface: N/A
FtnIndex: 0x0 TrafficIndex: N/A
Connector: N/A
The output shows that Switch A communicates with Switch B through VLAN-interface 11.
OSPF FRR configuration example
Network requirements
As shown in Figure 34, Switch A, Switch B, and Switch C reside in the same OSPF domain. Configure OSPF FRR so that when the link between Switch A and Switch B fails, traffic is immediately switched to Link B.
Table 10 Interface and IP address assignment
Device |
Interface |
IP address |
Switch A |
Vlan-int100 |
12.12.12.1/24 |
Switch A |
Vlan-int200 |
13.13.13.1/24 |
Switch A |
Loop0 |
1.1.1.1/32 |
Switch B |
Vlan-int101 |
24.24.24.4/24 |
Switch B |
Vlan-int200 |
13.13.13.2/24 |
Switch B |
Loop0 |
4.4.4.4/32 |
Switch C |
Vlan-int100 |
12.12.12.2/24 |
Switch C |
Vlan-int101 |
24.24.24.2/24 |
Configuration procedure
1. Configure IP addresses and subnet masks for interfaces on the switches. (Details not shown.)
2. Configure OSPF on the switches to ensure that Switch A, Switch B, and Switch C can communicate with each other at the network layer. (Details not shown.)
3. Configure OSPF FRR to automatically calculate the backup next hop:
You can enable OSPF FRR to either calculate a backup next hop by using the LFA algorithm, or specify a backup next hop by using a routing policy.
? (Method 1.) Enable OSPF FRR to calculate the backup next hop by using the LFA algorithm:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] ospf 1
[SwitchA-ospf-1] fast-reroute lfa
[SwitchA-ospf-1] quit
# Configure Switch B.
<SwitchB> system-view
[SwitchB] ospf 1
[SwitchB-ospf-1] fast-reroute lfa
[SwitchB-ospf-1] quit
? (Method 2.) Enable OSPF FRR to designate a backup next hop by using a routing policy.
# Configure Switch A.
<SwitchA> system-view
[SwitchA] ip prefix-list abc index 10 permit 4.4.4.4 32
[SwitchA] route-policy frr permit node 10
[SwitchA-route-policy-frr-10] if-match ip address prefix-list abc
[SwitchA-route-policy-frr-10] apply fast-reroute backup-interface vlan-interface 100 backup-nexthop 12.12.12.2
[SwitchA-route-policy-frr-10] quit
[SwitchA] ospf 1
[SwitchA-ospf-1] fast-reroute route-policy frr
[SwitchA-ospf-1] quit
# Configure Switch B.
<SwitchB> system-view
[SwitchB] ip prefix-list abc index 10 permit 1.1.1.1 32
[SwitchB] route-policy frr permit node 10
[SwitchB-route-policy-frr-10] if-match ip address prefix-list abc
[SwitchB-route-policy-frr-10] apply fast-reroute backup-interface vlan-interface 101 backup-nexthop 24.24.24.2
[SwitchB-route-policy-frr-10] quit
[SwitchB] ospf 1
[SwitchB-ospf-1] fast-reroute route-policy frr
[SwitchB-ospf-1] quit
Verifying the configuration
# Display route 4.4.4.4/32 on Switch A to view the backup next hop information.
[SwitchA] display ip routing-table 4.4.4.4 verbose
Summary Count : 1
Destination: 4.4.4.4/32
Protocol: O_INTRA
Process ID: 1
SubProtID: 0x1 Age: 04h20m37s
Cost: 1 Preference: 10
IpPre: N/A QosLocalID: N/A
Tag: 0 State: Active Adv
OrigTblID: 0x0 OrigVrf: default-vrf
TableID: 0x2 OrigAs: 0
NibID: 0x26000002 LastAs: 0
AttrID: 0xffffffff Neighbor: 0.0.0.0
Flags: 0x1008c OrigNextHop: 13.13.13.2
Label: NULL RealNextHop: 13.13.13.2
BkLabel: NULL BkNextHop: 12.12.12.2
Tunnel ID: Invalid Interface: Vlan-interface200
BkTunnel ID: Invalid BkInterface: Vlan-interface100
FtnIndex: 0x0 TrafficIndex: N/A
Connector: N/A
# Display route 1.1.1.1/32 on Switch B to view the backup next hop information.
[SwitchB] display ip routing-table 1.1.1.1 verbose
Summary Count : 1
Destination: 1.1.1.1/32
Protocol: O_INTRA
Process ID: 1
SubProtID: 0x1 Age: 04h20m37s
Cost: 1 Preference: 10
IpPre: N/A QosLocalID: N/A
Tag: 0 State: Active Adv
OrigTblID: 0x0 OrigVrf: default-vrf
TableID: 0x2 OrigAs: 0
NibID: 0x26000002 LastAs: 0
AttrID: 0xffffffff Neighbor: 0.0.0.0
Flags: 0x1008c OrigNextHop: 13.13.13.1
Label: NULL RealNextHop: 13.13.13.1
BkLabel: NULL BkNextHop: 24.24.24.2
Tunnel ID: Invalid Interface: Vlan-interface200
BkTunnel ID: Invalid BkInterface: Vlan-interface101
FtnIndex: 0x0 TrafficIndex: N/A
Connector: N/A
Troubleshooting OSPF configuration
No OSPF neighbor relationship established
Symptom
No OSPF neighbor relationship can be established.
Analysis
If the physical link and lower layer protocols work correctly, verify OSPF parameters configured on interfaces. Two neighbors must have the same parameters, such as the area ID, network segment, and mask. (A P2P or virtual link can have different network segments and masks.)
Solution
To resolve the problem:
1. Use the display ospf peer command to verify OSPF neighbor information.
2. Use the display ospf interface command to verify OSPF interface information.
3. Ping the neighbor router's IP address to verify that the connectivity is normal.
4. Verify OSPF timers. The dead interval on an interface must be a minimum of four times the hello interval.
5. On an NBMA network, use the peer ip-address command to manually specify the neighbor.
6. A minimum of one interface must have a router priority higher than 0 on an NBMA or a broadcast network.
7. If the problem persists, contact H3C Support.
Incorrect routing information
Symptom
OSPF cannot find routes to other areas.
Analysis
The backbone area must maintain connectivity to all other areas. If a router connects to more than one area, a minimum of one area must be connected to the backbone. The backbone cannot be configured as a stub area.
In a stub area, all routers cannot receive external routes, and all interfaces connected to the stub area must belong to the stub area.
Solution
To resolve the problem:
1. Use the display ospf peer command to verify neighbor information.
2. Use the display ospf interface command to verify OSPF interface information.
3. Use the display ospf lsdb command to verify the LSDB.
4. Use the display current-configuration configuration ospf command to verify area configuration. If more than two areas are configured, a minimum of one area is connected to the backbone.
5. In a stub area, all routers attached are configured with the stub command. In an NSSA area, all routers attached are configured with the nssa command.
6. If a virtual link is configured, use the display ospf vlink command to verify the state of the virtual link.
7. If the problem persists, contact H3C Support.
Configuring IS-IS
Overview
Intermediate System-to-Intermediate System (IS-IS) is a dynamic routing protocol designed by the ISO to operate on the connectionless network protocol (CLNP).
IS-IS was modified and extended in RFC 1195 by the IETF for application in both TCP/IP and OSI reference models, called "Integrated IS-IS" or "Dual IS-IS."
IS-IS is an IGP used within an AS. It uses the SPF algorithm for route calculation.
Terminology
· Intermediate system—Similar to a router in TCP/IP, IS is the basic unit used in an IS-IS routing domain to generate and propagate routing information. Throughout this chapter, an IS refers to a router.
· End system—Similar to a host in TCP/IP, an ES does not run IS-IS. ISO defines the ES-IS protocol for communication between an ES and an IS.
· Routing domain—An RD comprises a group of ISs that exchange routing information with each other by using the same routing protocol.
· Area—An IS-IS routing domain can be split into multiple areas.
· Link State Database—All link states in the network form the LSDB. Each IS has a minimum of one LSDB. An IS uses the SPF algorithm and LSDB to generate IS-IS routes.
· Link State Protocol Data Unit or Link State Packet —An IS advertises link state information in an LSP.
· Network Protocol Data Unit—An NPDU is a network layer protocol packet in OSI, similar to an IP packet in TCP/IP.
· Designated IS—A DIS is elected on a broadcast network.
· Network service access point—An NSAP is an OSI network layer address. The NSAP identifies an abstract network service access point and describes the network address format in the OSI reference model.
IS-IS address format
NSAP
As shown in Figure 35, an NSAP address comprises the Initial Domain Part (IDP) and the Domain Specific Part (DSP). The IDP is analogous to the network ID of an IP address, and the DSP is analogous to the subnet and host ID.
The IDP includes the Authority and Format Identifier (AFI) and the Initial Domain Identifier (IDI).
The DSP includes:
· High Order Part of DSP (HO-DSP)—Identifies the area.
· System ID—Identifies the host.
· SEL—Identifies the type of service.
The IDP and DSP are variable in length. The length of an NSAP address is in the range of 8 to 20 bytes.
Figure 35 NSAP address format
Area address
The area address comprises the IDP and the HO-DSP of the DSP, which identify the area and the routing domain. Different routing domains cannot have the same area address.
Typically, a router only needs one area address, and all nodes in the same area must have the same area address. To support smooth area merging, partitioning, and switching, a router can have a maximum of three area addresses.
System ID
A system ID uniquely identifies a host or router. It has a fixed length of 48 bits (6 bytes).
The system ID of a device can be generated from the router ID. For example, suppose a router uses the IP address 168.10.1.1 of Loopback 0 as the router ID. The system ID can be obtained in the following steps:
1. Extend each decimal number of the IP address to three digits by adding 0s from the left, such as 168.010.001.001.
2. Divide the extended IP address into three sections that each has four digits to get the system ID 1680.1000.1001.
If you use other methods to define a system ID, make sure that it can uniquely identify the host or router.
SEL
The N-SEL, or the NSAP selector (SEL), is similar to the protocol identifier in IP. Different transport layer protocols correspond to different SELs. All SELs in IP are 00.
Routing method
The IS-IS address format identifies the area, so a Level-1 router can easily identify packets destined to other areas. IS-IS routers perform routing as follows:
· A Level-1 router performs intra-area routing according to the system ID. If the destination address of a packet does not belong to the local area, the Level-1 router forwards it to the nearest Level-1-2 router.
· A Level-2 router performs inter-area routing according to the area address.
NET
A network entity title (NET) identifies the network layer information of an IS. It does not include transport layer information. A NET is a special NSAP address with the SEL being 0. The length of a NET is in the range of 8 to 20 bytes, same as a NSAP address.
A NET includes the following parts:
· Area ID—Has a length of 1 to 13 bytes.
· System ID—A system ID uniquely identifies a host or router in the area and has a fixed length of 6 bytes.
· SEL—Has a value of 0 and a fixed length of 1 byte.
For example, for a NET ab.cdef.1234.5678.9abc.00, the area ID is ab.cdef, the system ID is 1234.5678.9abc, and the SEL is 00.
Typically, a router only needs one NET, but it can have a maximum of three NETs for smooth area merging and partitioning. When you configure multiple NETs, make sure the system IDs are the same.
IS-IS area
IS-IS has a 2-level hierarchy to support large-scale networks. A large-scale routing domain is divided into multiple areas. Typically, a Level-1 router is deployed within an area. A Level-2 router is deployed between areas. A Level-1-2 router is deployed between Level-1 and Level-2 routers.
Level-1 and Level-2
· Level-1 router—A Level-1 router establishes neighbor relationships with Level-1 and Level-1-2 routers in the same area. It maintains an LSDB comprising intra-area routing information. A Level-1 router forwards packets destined for external areas to the nearest Level-1-2 router. Level-1 routers in different areas cannot establish neighbor relationships.
· Level-2 router—A Level-2 router establishes neighbor relationships with Level-2 and Level-1-2 routers in the same area or in different areas. It maintains a Level-2 LSDB containing inter-area routing information. All the Level-2 and Level-1-2 routers must be contiguous to form the backbone of the IS-IS routing domain. Level-2 routers can establish neighbor relationships even if they are in different areas.
· Level-1-2 router—A router with both Level-1 and Level-2 router functions is a Level-1-2 router. It can establish Level-1 neighbor relationships with Level-1 and Level-1-2 routers in the same area. It can establish Level-2 neighbor relationships with Level-2 and Level-1-2 routers in different areas. A Level-1 router can reach other areas only through a Level-1-2 router. The Level-1-2 router maintains two LSDBs, a Level-1 LSDB for intra-area routing and a Level-2 LSDB for inter-area routing.
Figure 36 shows one IS-IS network topology. Area 1 is the backbone that comprises a set of Level-2 routers. The other four areas are non-backbone areas connected to the backbone through Level-1-2 routers.
Figure 37 shows another IS-IS topology. The Level-1-2 routers connect to the Level-1 and Level-2 routers, and form the IS-IS backbone together with the Level-2 routers. No area is defined as the backbone in this topology. The backbone comprises all contiguous Level-2 and Level-1-2 routers in different areas. The IS-IS backbone does not need to be a specific area.
Both the Level-1 and Level-2 routers use the SPF algorithm to generate the shortest path tree.
Route leaking
Level-2 and Level-1-2 routers form a Level-2 area. An IS-IS routing domain comprises only one Level-2 area and multiple Level-1 areas. A Level-1 area must connect to the Level-2 area rather than another Level-1 area.
Level-1-2 routers send the routing information of Level-1 areas to the Level-2 area. Level-2 routers know the routing information of the entire IS-IS routing domain. By default, a Level-2 router does not advertise the routing information of other areas to a Level-1 area. A Level-1 router simply sends packets destined for other areas to the nearest Level-1-2 router. The path passing through the Level-1-2 router might not be the best. To solve this problem, IS-IS provides the route leaking feature.
Route leaking enables a Level-1-2 router to advertise the routes of other areas to the connected Level-1 area so that the Level-1 routers can select the optimal routes.
IS-IS network types
Network types
IS-IS supports broadcast networks (for example, Ethernet and Token Ring) and point-to-point networks (for example, PPP and HDLC).
For an NBMA interface, such as an ATM interface, you must configure point-to-point or broadcast subinterfaces. IS-IS cannot run on P2MP links.
DIS and pseudonodes
IS-IS routers on a broadcast network must elect a DIS.
The Level-1 and Level-2 DISs are elected separately. You can assign different priorities to a router for different level DIS elections. The higher the router priority, the more likely the router becomes the DIS. If multiple routers with the same highest DIS priority exist, the one with the highest Subnetwork Point of Attachment (SNPA) address will be elected. On a broadcast network, the SNPA address is the MAC address. A router can be the DIS for different levels.
IS-IS DIS election differs from OSPF DIS election in the following ways:
· A router with priority 0 can also participate in the DIS election.
· When a router with a higher priority is added to the network, an LSP flooding process is performed to elect the router as the new DIS.
As shown in Figure 38, the same level routers on a network, including non-DIS routers, establish adjacency with each other.
Figure 38 DIS in the IS-IS broadcast network
The DIS creates and updates pseudonodes, and generates LSPs for the pseudonodes, to describe all routers on the network.
A pseudonode represents a virtual node on the broadcast network. It is not a real router. In IS-IS, it is identified by the system ID of the DIS and a 1-byte Circuit ID (a non-zero value).
Using pseudonodes simplifies network topology and can reduce the amount of resources consumed by SPF.
|
NOTE: On an IS-IS broadcast network, all routers establish adjacency relationships, but they synchronize their LSDBs through the DIS. |
IS-IS PDUs
PDU
IS-IS PDUs are encapsulated into link layer frames. An IS-IS PDU has two parts, the headers and the variable length fields. The headers comprise the PDU common header and the PDU specific header. All PDUs have the same PDU common header. The specific headers vary by PDU type.
Figure 39 PDU format
Table 11 PDU types
Type |
PDU Type |
Acronym |
15 |
Level-1 LAN IS-IS hello PDU |
L1 LAN IIH |
16 |
Level-2 LAN IS-IS hello PDU |
L2 LAN IIH |
17 |
Point-to-Point IS-IS hello PDU |
P2P IIH |
18 |
Level-1 Link State PDU |
L1 LSP |
20 |
Level-2 Link State PDU |
L2 LSP |
24 |
Level-1 Complete Sequence Numbers PDU |
L1 CSNP |
25 |
Level-2 Complete Sequence Numbers PDU |
L2 CSNP |
26 |
Level-1 Partial Sequence Numbers PDU |
L1 PSNP |
27 |
Level-2 Partial Sequence Numbers PDU |
L2 PSNP |
Hello PDU
IS-to-IS hello (IIH) PDUs are used by routers to establish and maintain neighbor relationships. On broadcast networks, Level-1 routers use Level-1 LAN IIHs, and Level-2 routers use Level-2 LAN IIHs. The P2P IIHs are used on point-to-point networks.
LSP
The LSPs carry link state information. LSPs include Level-1 LSPs and Level-2 LSPs. The Level-2 LSPs are sent by the Level-2 routers, and the Level-1 LSPs are sent by the Level-1 routers. The Level-1-2 router can send both types of LSPs.
SNP
A sequence number PDU (SNP) describes the complete or partial LSPs for LSDB synchronization.
SNPs include CSNP and PSNP, which are further divided into Level-1 CSNP, Level-2 CSNP, Level-1 PSNP, and Level-2 PSNP.
A CSNP describes the summary of all LSPs for LSDB synchronization between neighboring routers. On broadcast networks, CSNPs are sent by the DIS periodically (every 10 seconds by default). On point-to-point networks, CSNPs are sent only during the first adjacency establishment.
A PSNP only contains the sequence numbers of one or multiple latest received LSPs. It can acknowledge multiple LSPs at one time. When LSDBs are not synchronized, a PSNP is used to request missing LSPs from a neighbor.
CLV
The variable fields of PDU comprise multiple Code-Length-Value (CLV) triplets.
Figure 40 CLV format
Table 12 shows that different PDUs contain different CLVs. Codes 1 through 10 are defined in ISO 10589 (code 3 and 5 are not shown in the table). Codes 128 through 132 are defined in RFC 1195. Codes 222 through 237 are defined in RFC 5120.
Table 12 CLV codes and PDU types
CLV Code |
Name |
PDU Type |
1 |
Area Addresses |
IIH, LSP |
2 |
IS Neighbors (LSP) |
LSP |
4 |
Partition Designated Level 2 IS |
L2 LSP |
6 |
IS Neighbors (MAC Address) |
LAN IIH |
7 |
IS Neighbors (SNPA Address) |
LAN IIH |
8 |
Padding |
IIH |
9 |
LSP Entries |
SNP |
10 |
Authentication Information |
IIH, LSP, SNP |
128 |
IP Internal Reachability Information |
LSP |
129 |
Protocols Supported |
IIH, LSP |
130 |
IP External Reachability Information |
L2 LSP |
131 |
Inter-Domain Routing Protocol Information |
L2 LSP |
132 |
IP Interface Address |
IIH, LSP |
222 |
MT-ISN |
LSP |
229 |
M-Topologies |
IIH, LSP |
235 |
MT IP. Reach |
LSP |
237 |
MT IPv6 IP. Reach |
LSP |
Protocols and standards
· ISO 10589 ISO IS-IS Routing Protocol
· ISO 9542 ES-IS Routing Protocol
· ISO 8348/Ad2 Network Services Access Points
· RFC 1195, Use of OSI IS-IS for Routing in TCP/IP and Dual Environments
· RFC 2763, Dynamic Hostname Exchange Mechanism for IS-IS
· RFC 2966, Domain-wide Prefix Distribution with Two-Level IS-IS
· RFC 3277, IS-IS Transient Blackhole Avoidance
· RFC 3358, Optional Checksums in ISIS
· RFC 3373, Three-Way Handshake for IS-IS Point-to-Point Adjacencies
· RFC 3567, Intermediate System to Intermediate System (IS-IS) Cryptographic Authentication
· RFC 3719, Recommendations for Interoperable Networks using IS-IS
· RFC 3786, Extending the Number of IS-IS LSP Fragments Beyond the 256 Limit
· RFC 3787, Recommendations for Interoperable IP Networks using IS-IS
· RFC 3847, Restart Signaling for IS-IS
· RFC 4444, Management Information Base for Intermediate System to Intermediate System (IS-IS)
· RFC 5303, Three-Way Handshake for IS-IS Point-to-Point Adjacencies
· RFC 5310, IS-IS Generic Cryptographic Authentication
IS-IS configuration task list
Configuring basic IS-IS
Configuration prerequisites
Before the configuration, complete the following tasks:
· Configure the link layer protocol.
· Configure IP addresses for interfaces to ensure IP connectivity between neighboring nodes.
Enabling IS-IS
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enable IS-IS and enter IS-IS view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
By default, IS-IS is disabled. |
3. Assign a NET. |
network-entity net |
By default, NET is not assigned. |
4. Return to system view. |
quit |
N/A |
5. Enter interface view. |
interface interface-type interface-number |
N/A |
6. Enable IS-IS on the interface. |
isis enable [ process-id ] |
By default, IS-IS is disabled. |
Setting the IS level and circuit level
Follow these guidelines when you configure the IS level for routers in only one area:
· Set the IS level of all routers to Level-1 or Level-2 rather than different levels because the routers do not need to maintain two identical LSDBs.
· Set the IS level to Level-2 on all routers in an IP network for good scalability.
For an interface of a Level-1 or Level-2 router, the circuit level can only be Level-1 or Level-2. For an interface of a Level-1-2 router, the default circuit level is Level-1-2. If the router only needs to form Level-1 or Level-2 neighbor relationships, set the circuit level for its interfaces to Level-1 or Level-2. This will limit neighbor relationship establishment.
To configure the IS level and circuit level:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Specify the IS level. |
is-level { level-1 | level-1-2 | level-2 } |
By default, the IS level is Level-1-2. |
4. Return to system view. |
quit |
N/A |
5. Enter interface view. |
interface interface-type interface-number |
N/A |
6. Specify the circuit level. |
isis circuit-level [ level-1 | level-1-2 | level-2 ] |
By default, an interface can establish either the Level-1 or Level-2 adjacency. |
Configuring P2P network type for an interface
Perform this task only for a broadcast network that has up to two attached routers.
Interfaces with different network types operate differently. For example, broadcast interfaces on a network must elect the DIS and flood CSNP packets to synchronize the LSDBs. However, P2P interfaces on a network do not need to elect the DIS, and have a different LSDB synchronization mechanism.
If only two routers exist on a broadcast network, set the network type of attached interfaces to P2P. This avoids DIS election and CSNP flooding, saving network bandwidth and speeding up network convergence.
To configure P2P network type for an interface:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Configure P2P network type for an interface. |
isis circuit-type p2p |
By default, the network type of a VLAN interface is broadcast. |
Configuring IS-IS route control
Configuration prerequisites
Before the configuration, complete the following tasks:
· Configure IP addresses for interfaces to ensure IP connectivity between neighboring nodes.
· Enable IS-IS.
Configuring IS-IS link cost
The IS-IS cost of an interface is determined in the following order:
1. IS-IS cost specified in interface view.
2. IS-IS cost specified in system view.
The cost is applied to the interfaces associated with the IS-IS process.
3. Automatically calculated cost.
If the cost style is wide or wide-compatible, IS-IS automatically calculates the cost using the formula: Interface cost = (Bandwidth reference value / Expected interface bandwidth) × 10, in the range of 1 to 16777214. For other cost styles, Table 13 applies.
Configure the expected bandwidth of an interface with the bandwidth command. For more information, see Interface Command Reference.
Table 13 Automatic cost calculation scheme for cost styles other than wide and wide-compatible
Interface bandwidth |
Interface cost |
≤ 10 Mbps |
60 |
≤ 100 Mbps |
50 |
≤ 155 Mbps |
40 |
≤ 622 Mbps |
30 |
≤ 2500 Mbps |
20 |
> 2500 Mbps |
10 |
4. If none of the above costs is used, a default cost of 10 applies.
Configuring an IS-IS cost for an interface
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. (Optional.) Specify an IS-IS cost style. |
cost-style { narrow | wide | wide-compatible | { compatible | narrow-compatible } [ relax-spf-limit ] } |
By default, the IS-IS cost type is narrow. |
4. Return to system view. |
quit |
N/A |
5. Enter interface view. |
interface interface-type interface-number |
N/A |
6. Specify a cost for the IS-IS interface. |
isis cost cost-value [ level-1 | level-2 ] |
By default, no cost for the interface is specified. |
Configuring a global IS-IS cost
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Specify a global IS-IS cost. |
circuit-cost cost-value [ level-1 | level-2 ] |
By default, no global cost is specified. |
Enabling automatic IS-IS cost calculation
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Enable automatic IS-IS cost calculation. |
auto-cost enable |
By default, automatic IS-IS cost calculation is disabled. |
4. (Optional.) Configure a bandwidth reference value for automatic IS-IS cost calculation. |
bandwidth-reference value |
The default setting is 100 Mbps. |
Specifying a preference for IS-IS
If multiple routing protocols find routes to the same destination, the route found by the routing protocol that has the highest preference is selected as the optimal route.
Perform this task to assign a preference to IS-IS directly or by using a routing policy. For more information about the routing policy, see "Configuring routing policies."
To configure a preference for IS-IS:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS IPv4 unicast address family view. |
a isis [ process-id ] [ vpn-instance vpn-instance-name ] b cost-style { wide | wide-compatible } c address-family ipv4 [ unicast ] |
N/A |
3. Configure a preference for IS-IS. |
preference { preference | route-policy route-policy-name } * |
The default setting is 15. |
Configuring the maximum number of ECMP routes
Perform this task to implement load sharing over ECMP routes.
To configure the maximum number of ECMP routes:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS IPv4 unicast address family view. |
a isis [ process-id ] [ vpn-instance vpn-instance-name ] b cost-style { wide | wide-compatible } c address-family ipv4 [ unicast ] |
N/A |
3. Specify the maximum number of ECMP routes. |
maximum load-balancing number |
By default, the maximum number of IS-IS ECMP routes equals the maximum number of ECMP routes supported by the system. |
Configuring IS-IS route summarization
Perform this task to summarize specific routes, including IS-IS routes and redistributed routes, into a single route. Route summarization can reduce the routing table size and the LSDB scale.
Route summarization applies only to locally generated LSPs. The cost of the summary route is the lowest one among the costs of the more-specific routes.
To configure route summarization:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS IPv4 unicast address family view. |
a isis [ process-id ] [ vpn-instance vpn-instance-name ] b cost-style { wide | wide-compatible } c address-family ipv4 [ unicast ] |
N/A |
3. Configure IS-IS route summarization. |
summary ip-address { mask-length | mask } [ avoid-feedback | generate_null0_route | [ level-1 | level-1-2 | level-2 ] | tag tag ] * |
By default, route summarization is not configured. |
Advertising a default route
IS-IS cannot redistribute a default route to its neighbors. This task enables IS-IS to advertise a default route of 0.0.0.0/0 in an LSP to the same-level neighbors. Upon receiving the default route, the neighbors add it into their routing table.
To advertise a default route:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS IPv4 unicast address family view. |
a isis [ process-id ] [ vpn-instance vpn-instance-name ] b cost-style { wide | wide-compatible } c address-family ipv4 [ unicast ] |
N/A |
3. Advertise a Level-1 or Level-2 default route. |
default-route-advertise [ [ level-1 | level-1-2 | level-2 ] | route-policy route-policy-name ] * |
By default, IS-IS does not advertise a Level-1 or Level-2 default route. |
Configuring IS-IS route redistribution
Perform this task to redistribute routes from other routing protocols into IS-IS. You can specify a cost for redistributed routes and specify the maximum number of redistributed routes.
To configure IS-IS route redistribution from other routing protocols:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS IPv4 unicast address family view. |
a isis [ process-id ] [ vpn-instance vpn-instance-name ] b cost-style { wide | wide-compatible } c address-family ipv4 [ unicast ] |
N/A |
3. Redistribute routes from other routing protocols or other IS-IS processes. |
import-route protocol [ as-number ] [ process-id | all-processes | allow-ibgp ] [ allow-direct | cost cost-value | cost-type { external | internal } | [ level-1 | level-1-2 | level-2 ] | route-policy route-policy-name | tag tag ] * |
By default, no route is redistributed. By default, if no level is specified, this command redistributes routes into the Level-2 routing table. This command redistributes only active routes. To display active routes, use the display ip routing-table protocol command. |
4. (Optional.) Configure the maximum number of redistributed Level 1/Level 2 IPv4 routes. |
import-route limit number |
By default, the maximum number of redistributed Level 1/Level 2 IPv4 routes is not configured. |
Configuring IS-IS route filtering
You can use an ACL, IP prefix list, or routing policy to filter routes calculated using received LSPs and routes redistributed from other routing protocols.
Filtering routes calculated from received LSPs
IS-IS saves LSPs received from neighbors in the LSDB, and uses the SPF algorithm to calculate the shortest path tree with itself as the root. IS-IS installs the calculated routes to the IS-IS routing table and the optimal routes to the IP routing table.
Perform this task to filter calculated routes. Only routes that are not filtered can be added to the IP routing table. The filtered routes retain in the IS-IS routing table and can be advertised to neighbors.
To filter routes calculated using received LSPs:
Step |
Command |
Remarks |
|
1. Enter system view. |
system-view |
N/A |
|
2. Enter IS-IS IPv4 unicast address family view. |
a isis [ process-id ] [ vpn-instance vpn-instance-name ] b cost-style { wide | wide-compatible } c address-family ipv4 [ unicast ] |
N/A |
|
3. Filter routes calculated using received LSPs. |
filter-policy { ipv4-acl-number | prefix-list prefix-list-name | route-policy route-policy-name } import |
By default, IS-IS route filtering is not configured. |
|
Filtering redistributed routes
IS-IS can redistribute routes from other routing protocols or other IS-IS processes, add them to the IS-IS routing table, and advertise them in LSPs.
Perform this task to filter redistributed routes. Only routes that are not filtered can be added to the IS-IS routing table and advertised to neighbors.
To filter redistributed routes:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS IPv4 unicast address family view. |
a isis [ process-id ] [ vpn-instance vpn-instance-name ] b cost-style { wide | wide-compatible } c address-family ipv4 [ unicast ] |
N/A |
3. Filter routes redistributed from other routing protocols or IS-IS processes. |
filter-policy { ipv4-acl-number | prefix-list prefix-list-name | route-policy route-policy-name } export [ protocol [ process-id ] ] |
By default, IS-IS route filtering is not configured. |
Configuring IS-IS route leaking
Perform this task to control route advertisement (route leaking) between Level-1 and Level-2.
You can configure IS-IS to advertise routes from Level-2 to Level-1, and to not advertise routes from Level-1 to Level-2.
To configure IS-IS route leaking:
Step |
Command |
Remarks |
||
1. Enter system view. |
system-view |
N/A |
||
2. Enter IS-IS IPv4 unicast address family view. |
a isis [ process-id ] [ vpn-instance vpn-instance-name ] b cost-style { wide | wide-compatible } c address-family ipv4 [ unicast ] |
N/A |
||
3. Configure route leaking from Level-1 to Level-2. |
import-route isis level-1 into level-2 [ filter-policy { ipv4-acl-number | prefix-list prefix-list-name | route-policy route-policy-name } | tag tag ] * |
By default, IS-IS advertises routes from Level-1 to Level-2. |
||
4. Configure route leaking from Level-2 to Level-1. |
import-route isis level-2 into level-1 [ filter-policy { ipv4-acl-number | prefix-list prefix-list-name | route-policy route-policy-name } | tag tag ] * |
By default, IS-IS does not advertise routes from Level-2 to Level-1. |
||
Tuning and optimizing IS-IS networks
Configuration prerequisites
Before you tune and optimize IS-IS networks, complete the following tasks:
· Configure IP addresses for interfaces to ensure IP connectivity between neighboring nodes.
· Enable IS-IS.
Specifying the interval for sending IS-IS hello packets
If a neighbor does not receive any hello packets from the router within the advertised hold time, it considers the router down and recalculates the routes. The hold time is the hello multiplier multiplied by the hello interval.
To specify the interval for sending hello packets:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Specify the interval for sending hello packets. |
isis timer hello seconds [ level-1 | level-2 ] |
The default setting is 10 seconds. The interval between hello packets sent by the DIS is 1/3 the hello interval set with the isis timer hello command. |
Specifying the IS-IS hello multiplier
The hello multiplier is the number of hello packets a neighbor must miss before it declares that the router is down.
If a neighbor receives no hello packets from the router within the advertised hold time, it considers the router down and recalculates the routes. The hold time is the hello multiplier multiplied by the hello interval.
On a broadcast link, Level-1 and Level-2 hello packets are advertised separately. You must set a hello multiplier for each level.
On a P2P link, Level-1 and Level-2 hello packets are advertised in P2P hello packets. You do not need to specify Level-1 or Level-2.
To specify the IS-IS hello multiplier:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Specify the hello multiplier. |
isis timer holding-multiplier value [ level-1 | level-2 ] |
The default setting is 3. |
Specifying the interval for sending IS-IS CSNP packets
On a broadcast network, perform this task on the DIS that uses CSNP packets to synchronize LSDBs.
To specify the interval for sending IS-IS CSNP packets:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Specify the interval for sending CSNP packets on the DIS of a broadcast network. |
isis timer csnp seconds [ level-1 | level-2 ] |
The default setting is 10 seconds. |
Configuring a DIS priority for an interface
On a broadcast network, IS-IS must elect a router as the DIS at a routing level. You can specify a DIS priority at a level for an interface. The greater the interface's priority, the more likely it becomes the DIS. If multiple routers in the broadcast network have the same highest DIS priority, the router with the highest MAC address becomes the DIS.
To configure a DIS priority for an interface:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Configure a DIS priority for the interface. |
isis dis-priority priority [ level-1 | level-2 ] |
The default setting is 64. |
Disabling an interface from sending/receiving IS-IS packets
After being disabled from sending and receiving hello packets, an interface cannot form any neighbor relationship, but can advertise directly connected networks in LSPs through other interfaces. This can save bandwidth and CPU resources, and ensures that other routers know networks directly connected to the interface.
To disable an interface from sending and receiving IS-IS packets:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Disable the interface from sending and receiving IS-IS packets. |
isis silent |
By default, the interface can send and receive IS-IS packets. |
Enabling an interface to send small hello packets
IS-IS messages cannot be fragmented at the IP layer because they are directly encapsulated in frames. Any two IS-IS neighboring routers must negotiate a common MTU. To avoid sending big hellos to save bandwidth, enable the interface to send small hello packets without CLVs.
To enable an interface to send small hello packets:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Enable the interface to send small hello packets without CLVs. |
isis small-hello |
By default, the interface can send standard hello packets. |
Configuring LSP parameters
Configuring LSP timers
1. Specify the maximum age of LSPs.
Each LSP has an age that decreases in the LSDB. Any LSP with an age of 0 is deleted from the LSDB. You can adjust the age value based on the scale of a network.
To specify the maximum age of LSPs:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Specify the maximum LSP age. |
timer lsp-max-age seconds |
The default setting is 1200 seconds. |
2. Specify the LSP refresh interval and generation interval.
Each router needs to refresh its LSPs at a configurable interval and send them to other routers to prevent valid routes from aging out. A smaller refresh interval speeds up network convergence but consumes more bandwidth.
When network topology changes such as neighbor state, interface metric, system ID, or area ID changes occur, the router generates an LSP after a configurable interval. If such a change occurs frequently, excessive LSPs are generated, consuming a large amount of router resources and bandwidth. To solve the problem, you can adjust the LSP generation interval.
When network changes are not frequent, the minimum-interval is adopted. If network changes become frequent, the LSP generation interval increases by incremental-interval × 2n-2 (n is the number of calculation times) each time a generation occurs until the maximum-interval is reached.
To specify the LSP refresh interval and generation interval:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Specify the LSP refresh interval. |
timer lsp-refresh seconds |
By default, the LSP refresh interval is 900 seconds. |
4. Specify the LSP generation interval. |
timer lsp-generation maximum-interval [ minimum-interval [ incremental-interval ] ] [ level-1 | level-2 ] |
By default: · The maximum interval is 5 seconds. · The minimum interval is 50 milliseconds. · The incremental interval is 200 milliseconds. |
3. Specify LSP sending intervals.
If a change occurs in the LSDB, IS-IS advertises the changed LSP to neighbors. You can specify the minimum interval for sending these LSPs to control the amount of LSPs on the network.
On a P2P link, IS-IS requires an advertised LSP be acknowledged. If no acknowledgment is received within a configurable interval, IS-IS will retransmit the LSP.
To configure LSP sending intervals:
Step |
Command |
Remarks |
|
1. Enter system view. |
system-view |
N/A |
|
2. Enter interface view. |
interface interface-type interface-number |
N/A |
|
3. Specify the minimum interval for sending LSPs and the maximum LSP number that can be sent at a time. |
isis timer lsp time [ count count ] |
By default, the minimum interval is 33 milliseconds, and the maximum LSP number that can be sent at a time is 5. |
|
4. Specify the LSP retransmission interval on a P2P link. |
isis timer retransmit seconds |
By default, the LSP retransmission interval on a P2P link is 5 seconds. |
|
Specifying LSP lengths
IS-IS messages cannot be fragmented at the IP layer because they are directly encapsulated in frames. IS-IS routers in an area must send LSPs smaller than the smallest interface MTU in the area.
If the IS-IS routers have different interface MTUs, configure the maximum size of generated LSP packets to be smaller than the smallest interface MTU in the area. Without the configuration, the routers must dynamically adjust the LSP packet size to fit the smallest interface MTU, which takes time and affects other services.
To specify LSP lengths:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Specify the maximum length of generated Level-1 LSPs or Level-2 LSPs. |
lsp-length originate size [ level-1 | level-2 ] |
By default, the maximum length of generated Level-1 LSPs or Level-2 LSPs is 1497 bytes. |
4. Specify the maximum length of received LSPs. |
lsp-length receive size |
By default, the maximum length of received LSPs is 1497 bytes. |
Enabling LSP flash flooding
Changed LSPs can trigger SPF recalculation. To advertise the changed LSPs before the router recalculates routes for faster network convergence, enable LSP flash flooding.
To enable LSP flash flooding:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Enable LSP flash flooding. |
flash-flood [ flood-count flooding-count | max-timer-interval flooding-interval | [ level-1 | level-2 ] ] * |
By default, LSP flash flooding is disabled. |
Enabling LSP fragment extension
Perform this task to enable IS-IS fragment extension for an IS-IS process. The MTUs of all interfaces running the IS-IS process must not be less than 512. Otherwise, LSP fragment extension does not take effect.
To enable LSP fragment extension:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Enable LSP fragment extension. |
lsp-fragments-extend [ level-1 | level-1-2 | level-2 ] |
By default, this feature is disabled. |
4. Configure a virtual system ID. |
virtual-system virtual-system-id |
By default, no virtual system ID is configured. Configure a minimum of one virtual system to generate extended LSP fragments. |
Controlling SPF calculation interval
Based on the LSDB, an IS-IS router uses the SPF algorithm to calculate the shortest path tree with itself being the root, and uses the shortest path tree to determine the next hop to a destination network. By adjusting the SPF calculation interval, you can prevent bandwidth and router resources from being over consumed due to frequent topology changes.
When network changes are not frequent, the minimum-interval is adopted. If network changes become frequent, the SPF calculation interval increases by incremental-interval × 2n-2 (n is the number of calculation times) each time a calculation occurs until the maximum-interval is reached.
To control SPF calculation interval:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Configure the SPF calculation interval. |
timer spf maximum-interval [ minimum-interval [ incremental-interval ] ] |
By default: · The maximum interval is 5 seconds. · The minimum interval is 50 milliseconds. · The incremental interval is 200 milliseconds. |
Configuring convergence priorities for specific routes
A topology change causes IS-IS routing convergence. To improve convergence speed, you can assign convergence priorities to IS-IS routes. Convergence priority levels are critical, high, medium, and low. The higher the convergence priority, the faster the convergence speed.
By default, IS-IS host routes have medium convergence priority, and other IS-IS routes have low convergence priority.
To assign convergence priorities to specific IS-IS routes:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS IPv4 unicast address family view. |
a isis [ process-id ] [ vpn-instance vpn-instance-name ] b cost-style { wide | wide-compatible } c address-family ipv4 [ unicast ] |
N/A |
3. Assign convergence priorities to specific IS-IS routes. |
·
Method 1: ·
Method 2: |
By default, IS-IS routes, except IS-IS host routes, have the low convergence priority. |
Setting the LSDB overload bit
By setting the overload bit in sent LSPs, a router informs other routers of failures that make it unable to select routes and forward packets.
When an IS-IS router cannot record the complete LSDB, for example, because of memory insufficiency, it will calculate wrong routes. To make troubleshooting easier, temporarily isolate the router from the IS-IS network by setting the overload bit.
To set the LSDB overload bit:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Set the overload bit. |
set-overload [ on-startup [ [ start-from-nbr system-id [ timeout1 [ nbr-timeout ] ] ] | timeout2 | wait-for-bgp [ timeout3 ] ] ] [ allow { external | interlevel } * ] |
By default, the overload bit is not set. |
Configuring the ATT bit
A Level-1-2 router sends Level-1 LSPs with an ATT bit to inform the Level-1 routers that it can reach other areas.
Configuring IS-IS not to calculate the default route through the ATT bit
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Configure IS-IS not to calculate the default route through the ATT bit. |
ignore-att |
By default, IS-IS uses the ATT bit to calculate the default route. |
Setting the ATT bit of Level-1 LSPs
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS view |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Set the ATT bit of Level-1 LSPs. |
set-att { always | never } |
By default, the ATT bit is not set for Level-1 LSPs. |
Configuring the tag value for an interface
Perform this task when the link cost style is wide, wide-compatible, or compatible.
When IS-IS advertises a prefix with a tag value, IS-IS adds the tag to the IP reachability information TLV of the prefix.
To configure the tag value for an interface:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Configure the tag value for the interface. |
isis tag tag |
By default, the tag value of the interface is not configured. |
Configuring system ID to host name mappings
A 6-byte system ID in hexadecimal notation uniquely identifies a router or host in an IS-IS network. To make a system ID easy to read, the system allows you to use host names to identify devices. It also provides mappings between system IDs and host names.
The mappings can be configured manually or dynamically. Follow these guidelines when you configure the mappings:
· To view host names rather than system IDs by using the display isis lsdb command, you must enable dynamic system ID to host name mapping.
· If you configure both dynamic mapping and static mapping on a router, the host name specified for dynamic mapping applies.
Configuring a static system ID to host name mapping
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Configure a system ID to host name mapping for a remote IS. |
is-name map sys-id map-sys-name |
By default, no system ID to host name mapping is configured for a remote IS. A system ID can correspond to only one host name. |
Configuring dynamic system ID to host name mapping
Static system ID to host name mapping requires you to manually configure a mapping for each router in the network. When a new router is added to the network or a mapping must be modified, you must configure all routers manually.
When you use dynamic system ID to host name mapping, you only need to configure a host name for each router in the network. Each router advertises the host name in a dynamic host name CLV to other routers so all routers in the network can have all mappings.
To help check the origin of LSPs in the LSDB, you can configure a name for the DIS in a broadcast network.
To configure dynamic system ID to host name mapping:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Specify a host name for the IS and enable dynamic system ID to host name mapping. |
is-name sys-name |
By default, no host name is specified for the router. |
4. Return to system view. |
quit |
N/A |
5. Enter interface view. |
interface interface-type interface-number |
N/A |
6. Configure a DIS name. |
isis dis-name symbolic-name |
By default, no DIS name is configured. This command takes effect only on a router enabled with dynamic system ID to host name mapping. This command is not available on P2P interfaces. |
Enabling the logging of neighbor state changes
With this feature enabled, the router delivers logs about neighbor state changes to its information center. The information center processes the logs according to user-defined output rules (whether to output logs and where to output). For more information about the information center, see Network Management and Monitoring Configuration Guide.
To enable the logging of neighbor state changes:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Enable the logging of neighbor state changes. |
log-peer-change |
By default, the logging of neighbor state changes is enabled. |
Enabling IS-IS ISPF
When the network topology changes, Incremental Shortest Path First (ISPF) computes only the affected part of the SPT, instead of the entire SPT.
To enable IS-IS ISPF:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Enable IS-IS ISPF. |
ispf enable |
By default, IS-IS is disabled. |
Enabling prefix suppression
Perform this task to disable an interface from advertising its prefix in LSPs. This enhances network security by preventing IP routing to the interval nodes and speeds up network convergence.
To enable prefix suppression:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Enable prefix suppression on the interface. |
isis prefix-suppression |
By default, prefix suppression is disabled on the interface. This command is also applicable to the secondary IP address of the interface. |
Configuring IS-IS network management
This task includes the following configurations:
· Bind an IS-IS process to MIB so that you can use network management software to manage the specified IS-IS process.
· Enable IS-IS notifications to report important events.
To report critical IS-IS events to an NMS, enable SNMP notifications for IS-IS. For SNMP notifications to be sent correctly, you must also configure SNMP on the device. For more information about SNMP configuration, see the network management and monitoring configuration guide for the device.
To configure IS-IS network management:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Bind MIB to an IS-IS process. |
isis mib-binding process-id |
By default, MIB is bound to the IS-IS process with the smallest process ID. |
3. Enable IS-IS notification sending. |
snmp-agent trap enable isis [ adjacency-state-change | area-mismatch | authentication | authentication-type | buffsize-mismatch | id-length-mismatch | lsdboverload-state-change | lsp-corrupt | lsp-parse-error | lsp-size-exceeded | manual-address-drop | max-seq-exceeded | maxarea-mismatch | own-lsp-purge | protocol-support | rejected-adjacency | skip-sequence-number | version-skew ] * |
By default, IS-IS notification sending is enabled. |
4. Enter IS-IS view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
5. Configure the context name for the SNMP object for managing IS-IS. |
snmp context-name context-name |
By default, no context name is set for the SNMP object for managing IS-IS. |
Configuring IS-IS PIC
Prefix Independent Convergence (PIC) enables the device to speed up network convergence by ignoring the number of prefixes.
When both IS-IS PIC and IS-IS FRR are configured, IS-IS FRR takes effect.
IS-IS PIC applies only to LSPs sent by neighbors.
Enabling IS-IS PIC
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Enable PIC for IS-IS. |
pic [ additional-path-always ] |
By default, IS-IS PIC is enabled. |
Enabling BFD for IS-IS PIC
By default, IS-IS PIC does not use BFD to detect primary link failures. To speed up IS-IS convergence, enable BFD for IS-IS PIC to detect primary link failures.
To enable BFD control packet mode for IS-IS PIC:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Enable BFD control packet mode for IS-IS PIC. |
isis primary-path-detect bfd ctrl |
By default, BFD control packet mode is disabled for IS-IS PIC. |
To configure BFD echo packet mode for IS-IS PIC:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Configure the source IP address of BFD echo packets. |
bfd echo-source-ip ip-address |
By default, the source IP address of BFD echo packets is not configured. The source IP address cannot be on the same network segment as any local interface's IP address. For more information, see High Availability Command Reference. |
3. Enter interface view. |
interface interface-type interface-number |
N/A |
4. Enable BFD echo packet mode for IS-IS PIC. |
isis primary-path-detect bfd echo |
By default, BFD echo packet mode is disabled for IS-IS PIC. |
Enhancing IS-IS network security
To enhance the security of an IS-IS network, you can configure IS-IS authentication. IS-IS authentication involves neighbor relationship authentication, area authentication, and routing domain authentication.
Configuration prerequisites
Before the configuration, complete the following tasks:
· Configure IP addresses for interfaces to ensure IP connectivity between neighboring nodes.
· Enable IS-IS.
Configuring neighbor relationship authentication
With neighbor relationship authentication configured, an interface adds the key in the specified mode into hello packets to the peer and checks the key in the received hello packets. If the authentication succeeds, it forms the neighbor relationship with the peer.
The authentication mode and key at both ends must be identical.
To prevent packet exchange failure in case of an authentication key change, configure the interface not to check the authentication information in the received packets.
To configure neighbor relationship authentication:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Specify the authentication mode and key. |
isis authentication-mode { { gca key-id { hmac-sha-1 | hmac-sha-224 | hmac-sha-256 | hmac-sha-384 | hmac-sha-512 } [ nonstandard ] | md5 | simple } { cipher | plain } string | keychain keychain-name } [ level-1 | level-2 ] [ ip | osi ] |
By default, no authentication is configured. |
4. (Optional.) Configure the interface not to check the authentication information in the received hello packets. |
isis authentication send-only [ level-1 | level-2 ] |
When the authentication mode and key are configured, the interface checks the authentication information in the received packets by default. |
Configuring area authentication
Area authentication prevents the router from installing routing information from untrusted routers into the Level-1 LSDB. The router encapsulates the authentication key in the specified mode in Level-1 packets (LSP, CSNP, and PSNP). It also checks the key in received Level-1 packets.
Routers in a common area must have the same authentication mode and key.
To prevent packet exchange failure in case of an authentication key change, configure IS-IS not to check the authentication information in the received packets.
To configure area authentication:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Specify the area authentication mode and key. |
area-authentication-mode { { gca key-id { hmac-sha-1 | hmac-sha-224 | hmac-sha-256 | hmac-sha-384 | hmac-sha-512 } [ nonstandard ] | md5 | simple } { cipher | plain } string | keychain keychain-name } [ ip | osi ] |
By default, no area authentication is configured. |
4. (Optional.) Configure the interface not to check the authentication information in the received Level-1 packets, including LSPs, CSNPs, and PSNPs. |
area-authentication send-only |
When the authentication mode and key are configured, the interface checks the authentication information in the received packets by default. |
Configuring routing domain authentication
Routing domain authentication prevents untrusted routing information from entering into a routing domain. A router with the authentication configured encapsulates the key in the specified mode into Level-2 packets (LSP, CSNP, and PSNP) and check the key in received Level-2 packets.
All the routers in the backbone must have the same authentication mode and key.
To prevent packet exchange failure in case of an authentication key change, configure IS-IS not to check the authentication information in the received packets.
To configure routing domain authentication:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Specify the routing domain authentication mode and key. |
domain-authentication-mode { { gca key-id { hmac-sha-1 | hmac-sha-224 | hmac-sha-256 | hmac-sha-384 | hmac-sha-512 } [ nonstandard ] | md5 | simple } { cipher | plain } string | keychain keychain-name } [ ip | osi ] |
By default, no routing domain authentication is configured. |
4. (Optional.) Configure the interface not to check the authentication information in the received Level-2 packets, including LSPs, CSNPs, and PSNPs. |
domain-authentication send-only |
When the authentication mode and key are configured, the interface checks the authentication information in the received packets by default. |
Configuring IS-IS GR
GR ensures forwarding continuity when a routing protocol restarts or an active/standby switchover occurs.
Two routers are required to complete a GR process. The following are router roles in a GR process.
· GR restarter—Graceful restarting router. It must have GR capability.
· GR helper—A neighbor of the GR restarter. It assists the GR restarter to complete the GR process. By default, the device acts as the GR helper.
Configure IS-IS GR on the GR restarter.
GR restarter uses the following timers:
· T1 timer—Specifies the times that GR restarter can send a Restart TLV with the RR bit set. When rebooted, the GR restarter sends a Restart TLV with the RR bit set to its neighbor. If the GR restarter receives a Restart TLV with the RA set from its neighbor before the T1 timer expires, the GR process starts. Otherwise, the GR process fails.
· T2 timer—Specifies the LSDB synchronization interval. Each LSDB has a T2 timer. The Level-1-2 router has a Level-1 timer and a Level-2 timer. If the LSDBs have not synchronized before the two timers expire, the GR process fails.
· T3 timer—Specifies the GR interval. The GR interval is set as the holdtime in hello PDUs. Within the interval, the neighbors maintain their adjacency with the GR restarter. If the GR process has not completed within the holdtime, the neighbors tear down the neighbor relationship and the GR process fails.
|
IMPORTANT: IS-IS GR and IS-IS NSR are mutually exclusive. Do not configure them at the same time. |
To configure GR on the GR restarter:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enable IS-IS and enter IS-IS view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Enable IS-IS GR. |
graceful-restart |
By default, the GR capability for IS-IS is disabled. |
4. (Optional.) Suppress the SA bit during restart. |
graceful-restart suppress-sa |
By default, the SA bit is not suppressed. By enabling the GR restarter to suppress the Suppress-Advertisement (SA) bit in the hello PDUs, the neighbors will still advertise their adjacency with the GR restarter. |
5. (Optional.) Configure the T1 timer. |
graceful-restart t1 seconds count count |
By default, the T1 timer is 3 seconds and can expire 10 times. |
6. (Optional.) Configure the T2 timer. |
graceful-restart t2 seconds |
By default, the T2 timer is 60 seconds. |
7. (Optional.) Configure the T3 timer. |
graceful-restart t3 seconds |
By default, the T2 timer is 300 seconds. |
Configuring IS-IS NSR
After an active/standby switchover, the GR restarter obtains routing information from its neighbors, and the IS-IS process must learn all the routes. If the network topology changes during the switchover, removed routes cannot be updated to the device, which can result in blackhole routes.
NSR solves the problem by backing up IS-IS link state information from the active process to the standby process. After an active/standby switchover, NSR can complete link state recovery and route regeneration without requiring the cooperation of other devices.
|
IMPORTANT: IS-IS NSR and IS-IS GR are mutually exclusive. Do not configure them at the same time. |
To configure IS-IS NSR:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Enable IS-IS NSR. |
non-stop-routing |
By default, IS-IS NSR is disabled. IS-IS NSR takes effect on a per-process basis. As a best practice, enable NSR for each IS-IS process. |
Configuring BFD for IS-IS
BFD provides a single mechanism to quickly detect and monitor the connectivity of links between IS-IS neighbors, reducing network convergence time. For more information about BFD, see High Availability Configuration Guide.
To configure BFD for IS-IS:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Enable IS-IS on an interface. |
isis enable [ process-id ] |
N/A |
4. Enable BFD on an IS-IS interface. |
isis bfd enable |
By default, an IS-IS interface is not enabled with BFD. |
Configuring IS-IS FRR
A link or router failure on a path can cause packet loss and routing loop. IS-IS FRR enables fast rerouting to minimize the failover time.
Figure 41 Network diagram for IS-IS FRR
In Figure 41, after you enable FRR on Router B, IS-IS automatically calculates or designates a backup next hop when a link failure is detected. In this way, packets are directed to the backup next hop to reduce traffic recovery time. Meanwhile, IS-IS calculates the shortest path based on the new network topology, and forwards packets over the path after network convergence.
You can assign a backup next hop for IS-IS FRR through the following ways:
· Enable IS-IS FRR to calculate a backup next hop through Loop Free Alternate (LFA) calculation.
· Designate a backup next hop with a routing policy for routes matching specific criteria.
Configuration prerequisites
Before you configure IS-IS FRR, complete the following tasks:
· Configure IP addresses for interfaces to ensure IP connectivity between neighboring nodes.
· Enable IS-IS.
Configuration guidelines
The LFA calculation of FRR and that of TE are mutually exclusive.
Configuration procedure
Configuring IS-IS FRR to calculate a backup next hop through LFA calculation
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. (Optional.) Disable LFA calculation on the interface. |
isis fast-reroute lfa-backup exclude |
By default, the interface participates in LFA calculation, and can be elected as a backup interface. |
4. Return to system view. |
quit |
N/A |
5. Enter IS-IS IPv4 unicast address family view. |
a isis [ process-id ] [ vpn-instance vpn-instance-name ] b cost-style { wide | wide-compatible } c address-family ipv4 [ unicast ] |
N/A |
6. Enable IS-IS FRR to calculate a backup next hop through LFA calculation. |
fast-reroute lfa |
By default, IS-IS FRR is disabled. |
Configuring IS-IS FRR using a routing policy
You can use the apply fast-reroute backup-interface command to specify a backup next hop in a routing policy for routes matching specific criteria. You can also perform this task to reference the routing policy for IS-IS FRR. For more information about the apply fast-reroute backup-interface command and routing policy configurations, see "Configuring routing policies."
To configure IS-IS FRR using a routing policy:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. (Optional.) Disable LFA calculation on the interface. |
isis fast-reroute lfa-backup exclude |
By default, the interface participates in LFA calculation, and can be elected as a backup interface. |
4. Return to system view. |
quit |
N/A |
5. Enter IS-IS IPv4 unicast address family view. |
a isis [ process-id ] [ vpn-instance vpn-instance-name ] b cost-style { wide | wide-compatible } c address-family ipv4 [ unicast ] |
N/A |
6. Enable IS-IS FRR using a routing policy. |
fast-reroute route-policy route-policy-name |
By default, this feature is not enabled. |
Enabling BFD for IS-IS FRR
By default, IS-IS FRR does not use BFD to detect primary link failures. To speed up IS-IS convergence, enable BFD for IS-IS FRR to detect primary link failures.
To enable BFD control packet mode for IS-IS FRR:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Enable BFD control packet mode for IS-IS FRR. |
isis primary-path-detect bfd ctrl |
By default, BFD control packet mode is disabled for IS-IS FRR. |
To enable BFD echo packet mode for IS-IS FRR:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Configure the source IP address of BFD echo packets. |
bfd echo-source-ip ip-address |
By default, the source IP address of BFD echo packets is not configured. The source IP address cannot be on the same network segment as any local interface's IP address. For more information, see High Availability Command Reference. |
3. Enter interface view. |
interface interface-type interface-number |
N/A |
4. Enable BFD echo packet mode for IS-IS FRR. |
isis primary-path-detect bfd echo |
By default, BFD echo packet mode is disabled for IS-IS FRR. |
Displaying and maintaining IS-IS
Execute display commands in any view and the reset command in user view.
Task |
Command |
Display IS-IS process information. |
display isis [ process-id ] |
(In standalone mode.) Display IS-IS GR log information. |
display isis event-log graceful-restart slot slot-number |
(In IRF mode.) Display IS-IS GR log information. |
display isis event-log graceful-restart chassis chassis-number slot slot-number |
Display the IS-IS GR status. |
display isis graceful-restart status [ level-1 | level-2 ] [ process-id ] |
Display IS-IS interface information. |
display isis interface [ [ interface-type interface-number ] [ verbose ] | statistics ] [ process-id ] |
Display IS-IS LSDB information. |
display isis lsdb [ [ level-1 | level-2 ] | local | lsp-id lspid | [ lsp-name lspname ] | verbose ] * [ process-id ] |
Display the host name-to-system ID mapping table. |
display isis name-table [ process-id ] |
(In standalone mode.) Display IS-IS NSR log information. |
display isis event-log non-stop-routing slot slot-number |
(In IRF mode.) Display IS-IS NSR log information. |
display isis event-log non-stop-routing chassis chassis-number slot slot-number |
Display the IS-IS NSR status. |
display isis non-stop-routing status |
Display IS-IS packet statistics. |
display isis packet { csnp | hello | lsp | psnp } [ verbose ] [ interface-type interface-number ] [ process-id ] |
Display IS-IS neighbor information. |
display isis peer [ statistics | verbose ] [ process-id ] |
Display IS-IS redistributed route information. |
display isis redistribute [ ipv4 [ ip-address mask-length ] ] [ level-1 | level-2 ] [ process-id ] |
Display IS-IS IPv4 routing information. |
display isis route [ ipv4 [ ip-address mask-length ] ] [ [ level-1 | level-2 ] | verbose ] * [ process-id ] |
Display IS-IS IPv4 topology information. |
display isis spf-tree [ ipv4 ] [ [ level-1 | level-2 ] | verbose ] * [ process-id ] |
Display IS-IS statistics. |
display isis statistics [ ipv4 ] [ level-1 | level-1-2 | level-2 ] [ process-id ] |
Display IS-IS route calculation log information. |
display isis event-log spf [ ipv4 [ topology topo-name ] ] [ [ level-1 | level-2 ] | verbose ] * [ process-id ] |
Display IS-IS LSP log information. |
display isis event-log lsp [ level-1 | level-2 ] * [ process-id ] |
(In standalone mode.) Display OSI connection information. |
display osi [ slot slot-number ] |
(In IRF mode.) Display OSI connection information. |
display osi [ chassis chassis-number slot slot-number ] |
(In standalone mode.) Display OSI connection statistics. |
display osi statistics [ slot slot-number ] |
(In IRF mode.) Display OSI connection statistics. |
display osi statistics [ chassis chassis-number slot slot-number ] |
Clear IS-IS process data structure information. |
reset isis all [ process-id ] [ graceful-restart ] |
(In standalone mode.) Clear IS-IS GR log information. |
reset isis event-log graceful-restart slot slot-number |
(In IRF mode.) Clear IS-IS GR log information. |
reset isis event-log graceful-restart chassis chassis-number slot slot-number |
(In standalone mode.) Clear IS-IS NSR log information. |
reset isis event-log non-stop-routing slot slot-number |
(In IRF mode.) Clear IS-IS NSR log information. |
reset isis event-log non-stop-routing chassis chassis-number slot slot-number |
Clear IS-IS LSP log information. |
reset isis event-log lsp [ process-id ] |
Clear IS-IS packet statistics. |
reset isis packet [ csnp | hello | lsp | psnp ] by-interface [ interface-type interface-number ] [ process-id ] display isis packet { csnp | hello | lsp | psnp } [ verbose ] [ process-id ] |
Clear the data structure information of an IS-IS neighbor. |
reset isis peer system-id [ process-id ] |
Clear OSI connection statistics. |
reset osi statistics |
IS-IS configuration examples
Basic IS-IS configuration example
Network requirements
As shown in Figure 42, Switch A, Switch B, Switch C, and Switch D reside in an IS-IS AS.
Switch A and B are Level-1 switches, Switch D is a Level-2 switch, and Switch C is a Level-1-2 switch. Switch A, Switch B, and Switch C are in Area 10, and Switch D is in Area 20.
Configuration procedure
1. Configure IP addresses for interfaces. (Details not shown.)
2. Configure IS-IS:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] isis 1
[SwitchA-isis-1] is-level level-1
[SwitchA-isis-1] network-entity 10.0000.0000.0001.00
[SwitchA-isis-1] quit
[SwitchA] interface vlan-interface 100
[SwitchA-Vlan-interface100] isis enable 1
[SwitchA-Vlan-interface100] quit
# Configure Switch B.
<SwitchB> system-view
[SwitchB] isis 1
[SwitchB-isis-1] is-level level-1
[SwitchB-isis-1] network-entity 10.0000.0000.0002.00
[SwitchB-isis-1] quit
[SwitchB] interface vlan-interface 200
[SwitchB-Vlan-interface200] isis enable 1
[SwitchB-Vlan-interface200] quit
# Configure Switch C.
<SwitchC> system-view
[SwitchC] isis 1
[SwitchC-isis-1] network-entity 10.0000.0000.0003.00
[SwitchC-isis-1] quit
[SwitchC] interface vlan-interface 100
[SwitchC-Vlan-interface100] isis enable 1
[SwitchC-Vlan-interface100] quit
[SwitchC] interface vlan-interface 200
[SwitchC-Vlan-interface200] isis enable 1
[SwitchC-Vlan-interface200] quit
[SwitchC] interface vlan-interface 300
[SwitchC-Vlan-interface300] isis enable 1
[SwitchC-Vlan-interface300] quit
# Configure Switch D.
<SwitchD> system-view
[SwitchD] isis 1
[SwitchD-isis-1] is-level level-2
[SwitchD-isis-1] network-entity 20.0000.0000.0004.00
[SwitchD-isis-1] quit
[SwitchD] interface vlan-interface 100
[SwitchD-Vlan-interface100] isis enable 1
[SwitchD-Vlan-interface100] quit
[SwitchD] interface vlan-interface 300
[SwitchD-Vlan-interface300] isis enable 1
[SwitchD-Vlan-interface300] quit
Verifying the configuration
# Display the IS-IS LSDB on each switch to verify the LSPs.
[SwitchA] display isis lsdb
Database information for IS-IS(1)
---------------------------------
Level-1 Link State Database
---------------------------
LSPID Seq Num Checksum Holdtime Length ATT/P/OL
--------------------------------------------------------------------------
0000.0000.0001.00-00* 0x00000004 0xdf5e 1096 68 0/0/0
0000.0000.0002.00-00 0x00000004 0xee4d 1102 68 0/0/0
0000.0000.0002.01-00 0x00000001 0xdaaf 1102 55 0/0/0
0000.0000.0003.00-00 0x00000009 0xcaa3 1161 111 1/0/0
0000.0000.0003.01-00 0x00000001 0xadda 1112 55 0/0/0
*-Self LSP, +-Self LSP(Extended), ATT-Attached, P-Partition, OL-Overload
[SwitchB] display isis lsdb
Database information for IS-IS(1)
---------------------------------
Level-1 Link State Database
---------------------------
LSPID Seq Num Checksum Holdtime Length ATT/P/OL
--------------------------------------------------------------------------
0000.0000.0001.00-00 0x00000006 0xdb60 988 68 0/0/0
0000.0000.0002.00-00* 0x00000008 0xe651 1189 68 0/0/0
0000.0000.0002.01-00* 0x00000005 0xd2b3 1188 55 0/0/0
0000.0000.0003.00-00 0x00000014 0x194a 1190 111 1/0/0
0000.0000.0003.01-00 0x00000002 0xabdb 995 55 0/0/0
*-Self LSP, +-Self LSP(Extended), ATT-Attached, P-Partition, OL-Overload
[SwitchC] display isis lsdb
Database information for IS-IS(1)
---------------------------------
Level-1 Link State Database
---------------------------
LSPID Seq Num Checksum Holdtime Length ATT/P/OL
--------------------------------------------------------------------------
0000.0000.0001.00-00 0x00000006 0xdb60 847 68 0/0/0
0000.0000.0002.00-00 0x00000008 0xe651 1053 68 0/0/0
0000.0000.0002.01-00 0x00000005 0xd2b3 1052 55 0/0/0
0000.0000.0003.00-00* 0x00000014 0x194a 1051 111 1/0/0
0000.0000.0003.01-00* 0x00000002 0xabdb 854 55 0/0/0
*-Self LSP, +-Self LSP(Extended), ATT-Attached, P-Partition, OL-Overload
Level-2 Link State Database
---------------------------
LSPID Seq Num Checksum Holdtime Length ATT/P/OL
--------------------------------------------------------------------------
0000.0000.0003.00-00* 0x00000012 0xc93c 842 100 0/0/0
0000.0000.0004.00-00 0x00000026 0x331 1173 84 0/0/0
0000.0000.0004.01-00 0x00000001 0xee95 668 55 0/0/0
*-Self LSP, +-Self LSP(Extended), ATT-Attached, P-Partition, OL-Overload
[SwitchD] display isis lsdb
Database information for IS-IS(1)
---------------------------------
Level-2 Link State Database
---------------------------
LSPID Seq Num Checksum Holdtime Length ATT/P/OL
-------------------------------------------------------------------------------
0000.0000.0003.00-00 0x00000013 0xc73d 1003 100 0/0/0
0000.0000.0004.00-00* 0x0000003c 0xd647 1194 84 0/0/0
0000.0000.0004.01-00* 0x00000002 0xec96 1007 55 0/0/0
*-Self LSP, +-Self LSP(Extended), ATT-Attached, P-Partition, OL-Overload
# Display the IS-IS routing information on each switch.
[SwitchA] display isis route
Route information for IS-IS(1)
------------------------------
Level-1 IPv4 Forwarding Table
-----------------------------
IPv4 Destination IntCost ExtCost ExitInterface NextHop Flags
-------------------------------------------------------------------------------
10.1.1.0/24 10 NULL Vlan100 Direct D/L/-
10.1.2.0/24 20 NULL Vlan100 10.1.1.1 R/-/-
192.168.0.0/24 20 NULL Vlan100 10.1.1.1 R/-/-
0.0.0.0/0 10 NULL Vlan100 10.1.1.1 R/-/-
Flags: D-Direct, R-Added to Rib, L-Advertised in LSPs, U-Up/Down Bit Set
[SwitchC] display isis route
Route information for IS-IS(1)
------------------------------
Level-1 IPv4 Forwarding Table
-----------------------------
IPv4 Destination IntCost ExtCost ExitInterface NextHop Flags
-------------------------------------------------------------------------------
192.168.0.0/24 10 NULL Vlan300 Direct D/L/-
10.1.1.0/24 10 NULL Vlan100 Direct D/L/-
10.1.2.0/24 10 NULL Vlan200 Direct D/L/-
Flags: D-Direct, R-Added to Rib, L-Advertised in LSPs, U-Up/Down Bit Set
Level-2 IPv4 Forwarding Table
-----------------------------
IPv4 Destination IntCost ExtCost ExitInterface NextHop Flags
-------------------------------------------------------------------------------
192.168.0.0/24 10 NULL D/L/-
10.1.1.0/24 10 NULL D/L/-
10.1.2.0/24 10 NULL D/L/-
172.16.0.0/16 20 NULL Vlan300 192.168.0.2 R/-/-
Flags: D-Direct, R-Added to Rib, L-Advertised in LSPs, U-Up/Down Bit Set
[SwitchD] display isis route
Route information for IS-IS(1)
------------------------------
Level-2 IPv4 Forwarding Table
-----------------------------
IPv4 Destination IntCost ExtCost ExitInterface NextHop Flags
-------------------------------------------------------------------------------
192.168.0.0/24 10 NULL Vlan300 Direct D/L/-
10.1.1.0/24 20 NULL Vlan300 192.168.0.1 R/-/-
10.1.2.0/24 20 NULL Vlan300 192.168.0.1 R/-/-
172.16.0.0/16 10 NULL Vlan100 Direct D/L/-
Flags: D-Direct, R-Added to Rib, L-Advertised in LSPs, U-Up/Down Bit Set
The output shows that the routing table of Level-1 switches contains a default route with the next hop as the Level-1-2 switch. The routing table of Level-2 switch contains both routing information of Level-1 and Level-2.
DIS election configuration example
Network requirements
As shown in Figure 43, Switches A, B, C, and D reside in IS-IS area 10 on a broadcast network (Ethernet). Switch A and Switch B are Level-1-2 switches, Switch C is a Level-1 switch, and Switch D is a Level-2 switch.
Change the DIS priority of Switch A to make it elected as the Level-1-2 DIS router.
Configuration procedure
1. Configure IP addresses for interfaces. (Details not shown.)
2. Enable IS-IS:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] isis 1
[SwitchA-isis-1] network-entity 10.0000.0000.0001.00
[SwitchA-isis-1] quit
[SwitchA] interface vlan-interface 100
[SwitchA-Vlan-interface100] isis enable 1
[SwitchA-Vlan-interface100] quit
# Configure Switch B.
<SwitchB> system-view
[SwitchB] isis 1
[SwitchB-isis-1] network-entity 10.0000.0000.0002.00
[SwitchB-isis-1] quit
[SwitchB] interface vlan-interface 100
[SwitchB-Vlan-interface100] isis enable 1
[SwitchB-Vlan-interface100] quit
# Configure Switch C.
<SwitchC> system-view
[SwitchC] isis 1
[SwitchC-isis-1] network-entity 10.0000.0000.0003.00
[SwitchC-isis-1] is-level level-1
[SwitchC-isis-1] quit
[SwitchC] interface vlan-interface 100
[SwitchC-Vlan-interface100] isis enable 1
[SwitchC-Vlan-interface100] quit
# Configure Switch D.
<SwitchD> system-view
[SwitchD] isis 1
[SwitchD-isis-1] network-entity 10.0000.0000.0004.00
[SwitchD-isis-1] is-level level-2
[SwitchD-isis-1] quit
[SwitchD] interface vlan-interface 100
[SwitchD-Vlan-interface100] isis enable 1
[SwitchD-Vlan-interface100] quit
# Display information about IS-IS neighbors on Switch A.
[SwitchA] display isis peer
Peer information for IS-IS(1)
----------------------------
System Id: 0000.0000.0002
Interface: Vlan-interface100 Circuit Id: 0000.0000.0003.01
State: Up HoldTime: 21s Type: L1(L1L2) PRI: 64
System Id: 0000.0000.0003
Interface: Vlan-interface100 Circuit Id: 0000.0000.0003.01
State: Up HoldTime: 27s Type: L1 PRI: 64
System Id: 0000.0000.0002
Interface: Vlan-interface100 Circuit Id: 0000.0000.0004.01
State: Up HoldTime: 28s Type: L2(L1L2) PRI: 64
System Id: 0000.0000.0004
Interface: Vlan-interface100 Circuit Id: 0000.0000.0004.01
State: Up HoldTime: 30s Type: L2 PRI: 64
# Display information about IS-IS interfaces on Switch A.
[SwitchA] display isis interface
Interface information for IS-IS(1)
----------------------------------
Interface: Vlan-interface100
Index IPv4.State IPv6.State CircuitID MTU Type DIS
00001 Up Down 1 1497 L1/L2 No/No
# Display information about IS-IS interfaces on Switch C.
[SwitchC] display isis interface
Interface information for IS-IS(1)
----------------------------------
Interface: Vlan-interface100
Index IPv4.State IPv6.State CircuitID MTU Type DIS
00001 Up Down 1 1497 L1/L2 Yes/No
# Display information about IS-IS interfaces on Switch D.
[SwitchD] display isis interface
Interface information for IS-IS(1)
----------------------------------
Interface: Vlan-interface100
Index IPv4.State IPv6.State CircuitID MTU Type DIS
00001 Up Down 1 1497 L1/L2 No/Yes
The output shows that when the default DIS priority is used, Switch C is the DIS for Level-1, and Switch D is the DIS for Level-2. The pseudonodes of Level-1 and Level-2 are 0000.0000.0003.01 and 0000.0000.0004.01.
#Configure the DIS priority of Switch A.
[SwitchA] interface vlan-interface 100
[SwitchA-Vlan-interface100] isis dis-priority 100
[SwitchA-Vlan-interface100] quit
# Display IS-IS neighbors on Switch A.
[SwitchA] display isis peer
Peer information for IS-IS(1)
----------------------------
System Id: 0000.0000.0002
Interface: Vlan-interface100 Circuit Id: 0000.0000.0001.01
State: Up HoldTime: 21s Type: L1(L1L2) PRI: 64
System Id: 0000.0000.0003
Interface: Vlan-interface100 Circuit Id: 0000.0000.0001.01
State: Up HoldTime: 27s Type: L1 PRI: 64
System Id: 0000.0000.0002
Interface: Vlan-interface100 Circuit Id: 0000.0000.0001.01
State: Up HoldTime: 28s Type: L2(L1L2) PRI: 64
System Id: 0000.0000.0004
Interface: Vlan-interface100 Circuit Id: 0000.0000.0001.01
State: Up HoldTime: 30s Type: L2 PRI: 64
# Display information about IS-IS interfaces on Switch A.
[SwitchA] display isis interface
Interface information for IS-IS(1)
----------------------------------
Interface: Vlan-interface100
Index IPv4.State IPv6.State CircuitID MTU Type DIS
00001 Up Down 1 1497 L1/L2 Yes/Yes
The output shows that after the DIS priority configuration, Switch A becomes the DIS for Level-1-2, and the pseudonode is 0000.0000.0001.01.
# Display information about IS-IS neighbors and interfaces on Switch C.
[SwitchC] display isis peer
Peer information for IS-IS(1)
----------------------------
System Id: 0000.0000.0002
Interface: Vlan-interface100 Circuit Id: 0000.0000.0001.01
State: Up HoldTime: 25s Type: L1 PRI: 64
System Id: 0000.0000.0001
Interface: Vlan-interface100 Circuit Id: 0000.0000.0001.01
State: Up HoldTime: 7s Type: L1 PRI: 100
[SwitchC] display isis interface
Interface information for IS-IS(1)
----------------------------------
Interface: Vlan-interface100
Index IPv4.State IPv6.State CircuitID MTU Type DIS
00001 Up Down 1 1497 L1/L2 No/No
# Display information about IS-IS neighbors and interfaces on Switch D.
[SwitchD] display isis peer
Peer information for IS-IS(1)
----------------------------
System Id: 0000.0000.0001
Interface: Vlan-interface100 Circuit Id: 0000.0000.0001.01
State: Up HoldTime: 9s Type: L2 PRI: 100
System Id: 0000.0000.0002
Interface: Vlan-interface100 Circuit Id: 0000.0000.0001.01
State: Up HoldTime: 28s Type: L2 PRI: 64
[SwitchD] display isis interface
Interface information for IS-IS(1)
----------------------------------
Interface: Vlan-interface100
Index IPv4.State IPv6.State CircuitID MTU Type DIS
00001 Up Down 1 1497 L1/L2 No/No
IS-IS route redistribution configuration example
Network requirements
As shown in Figure 44, Switch A, Switch B, Switch C, and Switch D reside in the same AS. They use IS-IS to interconnect. Switch A and Switch B are Level-1 routers, Switch D is a Level-2 router, and Switch C is a Level-1-2 router.
Redistribute RIP routes into IS-IS on Switch D.
Configuration procedure
1. Configure IP addresses for interfaces. (Details not shown.)
2. Configure basic IS-IS:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] isis 1
[SwitchA-isis-1] is-level level-1
[SwitchA-isis-1] network-entity 10.0000.0000.0001.00
[SwitchA-isis-1] quit
[SwitchA] interface vlan-interface 100
[SwitchA-Vlan-interface100] isis enable 1
[SwitchA-Vlan-interface100] quit
# Configure Switch B.
<SwitchB> system-view
[SwitchB] isis 1
[SwitchB-isis-1] is-level level-1
[SwitchB-isis-1] network-entity 10.0000.0000.0002.00
[SwitchB-isis-1] quit
[SwitchB] interface vlan-interface 200
[SwitchB-Vlan-interface200] isis enable 1
[SwitchB-Vlan-interface200] quit
# Configure Switch C.
<SwitchC> system-view
[SwitchC] isis 1
[SwitchC-isis-1] network-entity 10.0000.0000.0003.00
[SwitchC-isis-1] quit
[SwitchC] interface vlan-interface 200
[SwitchC-Vlan-interface200] isis enable 1
[SwitchC-Vlan-interface200] quit
[SwitchC] interface vlan-interface 100
[SwitchC-Vlan-interface100] isis enable 1
[SwitchC-Vlan-interface100] quit
[SwitchC] interface vlan-interface 300
[SwitchC-Vlan-interface300] isis enable 1
[SwitchC-Vlan-interface300] quit
# Configure Switch D.
<SwitchD> system-view
[SwitchD] isis 1
[SwitchD-isis-1] is-level level-2
[SwitchD-isis-1] network-entity 20.0000.0000.0004.00
[SwitchD-isis-1] quit
[SwitchD] interface interface vlan-interface 300
[SwitchD-Vlan-interface300] isis enable 1
[SwitchD-Vlan-interface300] quit
[SwitchD] interface interface vlan-interface 400
[SwitchD-Vlan-interface400] isis enable 1
[SwitchD-Vlan-interface400] quit
# Display IS-IS routing information on each switch.
[SwitchA] display isis route
Route information for IS-IS(1)
------------------------------
Level-1 IPv4 Forwarding Table
-----------------------------
IPv4 Destination IntCost ExtCost ExitInterface NextHop Flags
-------------------------------------------------------------------------------
10.1.1.0/24 10 NULL VLAN100 Direct D/L/-
10.1.2.0/24 20 NULL VLAN100 10.1.1.1 R/-/-
192.168.0.0/24 20 NULL VLAN100 10.1.1.1 R/-/-
0.0.0.0/0 10 NULL VLAN100 10.1.1.1 R/-/-
Flags: D-Direct, R-Added to Rib, L-Advertised in LSPs, U-Up/Down Bit Set
[SwitchC] display isis route
Route information for IS-IS(1)
------------------------------
Level-1 IPv4 Forwarding Table
-----------------------------
IPv4 Destination IntCost ExtCost ExitInterface NextHop Flags
-------------------------------------------------------------------------------
10.1.1.0/24 10 NULL VLAN100 Direct D/L/-
10.1.2.0/24 10 NULL VLAN200 Direct D/L/-
192.168.0.0/24 10 NULL VLAN300 Direct D/L/-
Flags: D-Direct, R-Added to Rib, L-Advertised in LSPs, U-Up/Down Bit Set
Level-2 IPv4 Forwarding Table
-----------------------------
IPv4 Destination IntCost ExtCost ExitInterface NextHop Flags
-------------------------------------------------------------------------------
10.1.1.0/24 10 NULL D/L/-
10.1.2.0/24 10 NULL D/L/-
192.168.0.0/24 10 NULL D/L/-
Flags: D-Direct, R-Added to Rib, L-Advertised in LSPs, U-Up/Down Bit Set
[SwitchD] display isis route
Route information for IS-IS(1)
------------------------------
Level-2 IPv4 Forwarding Table
-----------------------------
IPv4 Destination IntCost ExtCost ExitInterface NextHop Flags
-------------------------------------------------------------------------------
192.168.0.0/24 10 NULL VLAN300 Direct D/L/-
10.1.1.0/24 20 NULL VLAN300 192.168.0.1 R/-/-
10.1.2.0/24 20 NULL VLAN300 192.168.0.1 R/-/-
Flags: D-Direct, R-Added to Rib, L-Advertised in LSPs, U-Up/Down Bit Set
3. Run RIPv2 between Switch D and Switch E, and configure IS-IS to redistribute RIP routes on Switch D:
# Configure RIPv2 on Switch D.
[SwitchD] rip 1
[SwitchD-rip-1] network 10.0.0.0
[SwitchD-rip-1] version 2
[SwitchD-rip-1] undo summary
# Configure RIPv2 on Switch E.
[SwitchE] rip 1
[SwitchE-rip-1] network 10.0.0.0
[SwitchE-rip-1] version 2
[SwitchE-rip-1] undo summary
# Configure IS-IS to redistribute RIP routes on Switch D.
[SwitchD-rip-1] quit
[SwitchD] isis 1
[SwitchD–isis-1] address-family ipv4
[SwitchD–isis-1-ipv4] import-route rip level-2
# Display IS-IS routing information on Switch C.
[SwitchC] display isis route
Route information for IS-IS(1)
------------------------------
Level-1 IPv4 Forwarding Table
-----------------------------
IPv4 Destination IntCost ExtCost ExitInterface NextHop Flags
-------------------------------------------------------------------------------
10.1.1.0/24 10 NULL VLAN100 Direct D/L/-
10.1.2.0/24 10 NULL VLAN200 Direct D/L/-
192.168.0.0/24 10 NULL VLAN300 Direct D/L/-
Flags: D-Direct, R-Added to Rib, L-Advertised in LSPs, U-Up/Down Bit Set
Level-2 IPv4 Forwarding Table
-----------------------------
IPv4 Destination IntCost ExtCost ExitInterface NextHop Flags
-------------------------------------------------------------------------------
10.1.1.0/24 10 NULL D/L/-
10.1.2.0/24 10 NULL D/L/-
192.168.0.0/24 10 NULL D/L/-
10.1.4.0/24 20 NULL VLAN300 192.168.0.2 R/L/-
10.1.5.0/24 10 0 VLAN300 192.168.0.2 R/L/-
10.1.6.0/24 10 0 VLAN300 192.168.0.2 R/L/-
Flags: D-Direct, R-Added to Rib, L-Advertised in LSPs, U-Up/Down Bit Set
IS-IS authentication configuration example
Network requirements
As shown in Figure 45, Switch A, Switch B, Switch C, and Switch D reside in the same IS-IS routing domain. Run IS-IS among them.
Switch A, Switch B, and Switch C belong to Area 10, and Switch D belongs to Area 20.
· Configure neighbor relationship authentication between neighbors.
· Configure area authentication in Area 10 to prevent untrusted routes from entering into the area.
· Configure routing domain authentication on Switch C and Switch D to prevent untrusted routes from entering the routing domain.
Configuration procedure
1. Configure IP addresses for interfaces. (Details not shown.)
2. Configure basic IS-IS:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] isis 1
[SwitchA-isis-1] network-entity 10.0000.0000.0001.00
[SwitchA-isis-1] quit
[SwitchA] interface vlan-interface 100
[SwitchA-Vlan-interface100] isis enable 1
[SwitchA-Vlan-interface100] quit
# Configure Switch B.
<SwitchB> system-view
[SwitchB] isis 1
[SwitchB-isis-1] network-entity 10.0000.0000.0002.00
[SwitchB-isis-1] quit
[SwitchB] interface vlan-interface 200
[SwitchB-Vlan-interface200] isis enable 1
[SwitchB-Vlan-interface200] quit
# Configure Switch C.
<SwitchC> system-view
[SwitchC] isis 1
[SwitchC-isis-1] network-entity 10.0000.0000.0003.00
[SwitchC-isis-1] quit
[SwitchC] interface vlan-interface 200
[SwitchC-Vlan-interface200] isis enable 1
[SwitchC-Vlan-interface200] quit
[SwitchC] interface vlan-interface 300
[SwitchC-Vlan-interface300] isis enable 1
[SwitchC-Vlan-interface300] quit
[SwitchC] interface vlan-interface 300
[SwitchC-Vlan-interface300] isis enable 1
[SwitchC-Vlan-interface300] quit
# Configure Switch D.
<SwitchD> system-view
[SwitchD] isis 1
[SwitchD-isis-1] network-entity 20.0000.0000.0001.00
[SwitchD-isis-1] quit
[SwitchD] interface vlan-interface 300
[SwitchD-Vlan-interface300] isis enable 1
[SwitchD-Vlan-interface300] quit
3. Configure neighbor relationship authentication between neighbors:
# Set the authentication mode to MD5 and set the plaintext key to eRq on VLAN-interface 100 of Switch A and on VLAN-interface 100 of Switch C.
[SwitchA] interface vlan-interface 100
[SwitchA-Vlan-interface100] isis authentication-mode md5 plain eRg
[SwitchA-Vlan-interface100] quit
[SwitchC] interface vlan-interface 100
[SwitchC-Vlan-interface100] isis authentication-mode md5 plain eRg
[SwitchC-Vlan-interface100] quit
# Set the authentication mode to MD5 and set the plaintext key to t5Hr on VLAN-interface 200 of Switch B and on VLAN-interface 200 of Switch C.
[SwitchB] interface vlan-interface 200
[SwitchB-Vlan-interface200] isis authentication-mode md5 plain t5Hr
[SwitchB-Vlan-interface200] quit
[SwitchC] interface vlan-interface 200
[SwitchC-Vlan-interface200] isis authentication-mode md5 plain t5Hr
[SwitchC-Vlan-interface200] quit
# Set the authentication mode to MD5 and set the plaintext key to hSec on VLAN-interface 300 of Switch D and on VLAN-interface 300 of Switch C.
[SwitchC] interface vlan-interface 300
[SwitchC-Vlan-interface300] isis authentication-mode md5 plain hSec
[SwitchC-Vlan-interface300] quit
[SwitchD] interface vlan-interface 300
[SwitchD-Vlan-interface300] isis authentication-mode md5 plain hSec
[SwitchD-Vlan-interface300] quit
4. Set the area authentication mode to MD5 and set the plaintext key to 10Sec on Switch A, Switch B, and Switch C.
[SwitchA] isis 1
[SwitchA-isis-1] area-authentication-mode md5 plain 10Sec
[SwitchA-isis-1] quit
[SwitchB] isis 1
[SwitchB-isis-1] area-authentication-mode md5 plain 10Sec
[SwitchB-isis-1] quit
[SwitchC] isis 1
[SwitchC-isis-1] area-authentication-mode md5 plain 10Sec
[SwitchC-isis-1] quit
5. Set routing domain authentication mode to MD5 and set the plaintext key to 1020Sec on Switch C and Switch D.
[SwitchC] isis 1
[SwitchC-isis-1] domain-authentication-mode md5 plain 1020Sec
[SwitchC-isis-1] quit
[SwitchD] isis 1
[SwitchD-isis-1] domain-authentication-mode md5 plain 1020Sec
IS-IS GR configuration example
Network requirements
As shown in Figure 46, Switch A, Switch B, and Switch C belong to the same IS-IS routing domain.
Configuration procedure
1. Configure IP addresses and subnet masks for interfaces. (Details not shown.)
2. Configure IS-IS on the switches to make sure Switch A, Switch B, and Switch C can communicate with each other at layer 3 and dynamic route update can be implemented among them with IS-IS. (Details not shown.)
3. Enable IS-IS GR on Switch A.
<SwitchA> system-view
[SwitchA] isis 1
[SwitchA-isis-1] graceful-restart
[SwitchA-isis-1] return
Verifying the configuration
# Restart the IS-IS process on Switch A.
<SwitchA> reset isis all 1 graceful-restart
Reset IS-IS process? [Y/N]:y
# Check the GR state of the IS-IS process on Switch A.
<SwitchA> display isis graceful-restart status
Restart information for IS-IS(1)
--------------------------------
Restart status: COMPLETE
Restart phase: Finish
Restart t1: 3, count 10; Restart t2: 60; Restart t3: 300
SA Bit: supported
Level-1 restart information
---------------------------
Total number of interfaces: 1
Number of waiting LSPs: 0
Level-2 restart information
---------------------------
Total number of interfaces: 1
Number of waiting LSPs: 0
IS-IS NSR configuration example
Network requirements
As shown in Figure 47, Switch S, Switch A, and Switch B belong to the same IS-IS routing domain.
· Run IS-IS on all the switches to interconnect them with each other.
· Enable IS-IS NSR on Switch S to ensure forwarding continuity between Switch A and Switch B when an active/standby switchover occurs on Switch S.
Configuration procedure
1. Configure the IP addresses and subnet masks for interfaces on the switches. (Details not shown.)
2. Configure IS-IS on the switches to make sure Switch S, Switch A, and Switch B can communicate with each other at Layer 3 and dynamic route update can be implemented among them with IS-IS. (Details not shown.)
3. Enable IS-IS NSR on Switch S.
<SwitchS> system-view
[SwitchS] isis 1
[SwitchS-isis-1] non-stop-routing
[SwitchS-isis-1] return
Verifying the configuration
# Reoptimize process placement on Switch S to trigger an active/standby switchover.
<SwitchS> system-view
[SwitchS] placement reoptimize
Predicted changes to the placement
Program Current location New location
---------------------------------------------------------------------
syslog 0/0 0/0
diagusageratio 0/0 0/0
l3vpn 0/0 0/0
dns 0/0 0/0
lauth 0/0 0/0
aaa 0/0 0/0
lsm 0/0 0/0
rm 0/0 0/0
rm6 0/0 0/0
track 0/0 0/0
ip6addr 0/0 0/0
ipaddr 0/0 0/0
rpm 0/0 0/0
trange 0/0 0/0
tunnel 0/0 0/0
lagg 0/0 0/0
bfd 0/0 0/0
acl 0/0 0/0
slsp 0/0 0/0
usr6 0/0 0/0
usr 0/0 0/0
qos 0/0 0/0
ethbase 0/0 0/0
ipcim 0/0 0/0
ip6base 0/0 0/0
ipbase 0/0 0/0
eth 0/0 0/0
ifnet NA NA
isis 0/0 1/0
Continue? [y/n]:y
Re-optimization of the placement start. You will be notified on completion
Re-optimization of the placement complete. Use 'display placement' to view the new placement
# During the switchover period, display IS-IS neighbor information on Switch A to verify the neighborship between Switch A and Switch S.
<SwitchA> display isis peer
Peer information for IS-IS(1)
----------------------------
System Id: 0000.0000.0001
Interface: vlan100 Circuit Id: 0000.0000.0001.01
State: Up HoldTime: 25s Type: L1(L1L2) PRI: 64
System Id: 0000.0000.0001
Interface: vlan100 Circuit Id: 0000.0000.0001.01
State: Up HoldTime: 27s Type: L2(L1L2) PRI: 64
# Display IS-IS routing information on Switch A to verify that Switch A has a route to the loopback interface of Switch B.
<SwitchA> display isis route
Route information for IS-IS(1)
-----------------------------
Level-1 IPv4 Forwarding Table
-----------------------------
IPv4 Destination IntCost ExtCost ExitInterface NextHop Flags
-------------------------------------------------------------------------------
12.12.12.0/24 10 NULL vlan100 Direct D/L/-
22.22.22.22/32 10 NULL Loop0 Direct D/-/-
14.14.14.0/32 10 NULL vlan100 12.12.12.2 R/L/-
44.44.44.44/32 10 NULL vlan100 12.12.12.2 R/L/-
Flags: D-Direct, R-Added to Rib, L-Advertised in LSPs, U-Up/Down Bit Set
Level-2 IPv4 Forwarding Table
-----------------------------
IPv4 Destination IntCost ExtCost ExitInterface NextHop Flags
-------------------------------------------------------------------------------
12.12.12.0/24 10 NULL vlan100 Direct D/L/-
22.22.22.22/32 10 NULL Loop0 Direct D/-/-
14.14.14.0/32 10 NULL
44.44.44.44/32 10 NULL
Flags: D-Direct, R-Added to Rib, L-Advertised in LSPs, U-Up/Down Bit Set
# Display IS-IS neighbor information on Switch B to verify the neighborship between Switch B and Switch S.
<SwitchB> display isis peer
Peer information for IS-IS(1)
----------------------------
System Id: 0000.0000.0001
Interface: vlan200 Circuit Id: 0000.0000.0001.01
State: Up HoldTime: 25s Type: L1(L1L2) PRI: 64
System Id: 0000.0000.0001
Interface: vlan200 Circuit Id: 0000.0000.0001.01
State: Up HoldTime: 27s Type: L2(L1L2) PRI: 64
# Display IS-IS routing information on Switch B to verify that Switch B has a route to the loopback interface of Switch A.
<SwitchB> display isis route
Route information for IS-IS(1)
-----------------------------
Level-1 IPv4 Forwarding Table
-----------------------------
IPv4 Destination IntCost ExtCost ExitInterface NextHop Flags
-------------------------------------------------------------------------------
14.14.14.0/24 10 NULL vlan200 Direct D/L/-
44.44.44.44/32 10 NULL Loop0 Direct D/-/-
12.12.12.0/32 10 NULL vlan200 14.14.14.4 R/L/-
22.22.22.22/32 10 NULL vlan200 14.14.14.4 R/L/-
Flags: D-Direct, R-Added to Rib, L-Advertised in LSPs, U-Up/Down Bit Set
Level-2 IPv4 Forwarding Table
-----------------------------
IPv4 Destination IntCost ExtCost ExitInterface NextHop Flags
-------------------------------------------------------------------------------
14.14.14.0/24 10 NULL vlan200 Direct D/L/-
44.44.44.44/32 10 NULL Loop0 Direct D/-/-
12.12.12.0/32 10 NULL
22.22.22.22/32 10 NULL
Flags: D-Direct, R-Added to Rib, L-Advertised in LSPs, U-Up/Down Bit Set
The output shows that the neighbor information and routing information on Switch A and Switch B have not changed during the active/standby switchover on Switch S. The neighbors are unaware of the switchover.
BFD for IS-IS configuration example
Network requirements
· As shown in Figure 48, run IS-IS on Switch A, Switch B and Switch C so that can reach each other at the network layer.
· After the link over which Switch A and Switch B communicate through the Layer-2 switch fails, BFD can quickly detect the failure and notify IS-IS of the failure. Switch A and Switch B then communicate through Switch C.
Table 14 Interface and IP address assignment
Device |
Interface |
IP address |
Device |
Interface |
IP address |
Switch A |
Vlan-int10 |
10.1.0.102/24 |
Switch B |
Vlan-int10 |
10.1.0.100/24 |
|
Vlan-int11 |
11.1.1.1/24 |
|
Vlan-int13 |
13.1.1.1/24 |
|
Loop0 |
121.1.1.1/32 |
|
Loop0 |
120.1.1.1/32 |
Switch C |
Vlan-int11 |
11.1.1.2/24 |
|
|
|
|
Vlan-int13 |
13.1.1.2/24 |
|
|
|
Configuration procedure
1. Configure IP addresses for interfaces. (Details not shown.)
2. Configure basic IS-IS:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] isis
[SwitchA-isis-1] network-entity 10.0000.0000.0001.00
[SwitchA-isis-1] quit
[SwitchA] interface loopback 0
[SwitchA-LoopBack0] isis enable
[SwitchA-LoopBack0] quit
[SwitchA] interface vlan-interface 10
[SwitchA-Vlan-interface10] isis enable
[SwitchA-Vlan-interface10] quit
[SwitchA] interface vlan-interface 11
[SwitchA-Vlan-interface11] isis enable
[SwitchA-Vlan-interface11] quit
# Configure Switch B.
<SwitchB> system-view
[SwitchB] isis
[SwitchB-isis-1] network-entity 10.0000.0000.0002.00
[SwitchB-isis-1] quit
[SwitchB] interface loopback 0
[SwitchB-LoopBack0] isis enable
[SwitchB-LoopBack0] quit
[SwitchB] interface vlan-interface 10
[SwitchB-Vlan-interface10] isis enable
[SwitchB-Vlan-interface10] quit
[SwitchB] interface vlan-interface 13
[SwitchB-Vlan-interface13] isis enable
[SwitchB-Vlan-interface13] quit
# Configure Switch C.
<SwitchC> system-view
[SwitchC] isis
[SwitchC-isis-1] network-entity 10.0000.0000.0003.00
[SwitchC-isis-1] quit
[SwitchC] interface vlan-interface 11
[SwitchC-Vlan-interface11] isis enable
[SwitchC-Vlan-interface11] quit
[SwitchC] interface vlan-interface 13
[SwitchC-Vlan-interface13] isis enable
[SwitchC-Vlan-interface13] quit
3. Configure BFD functions:
# Enable BFD and configure BFD parameters on Switch A.
[SwitchA] bfd session init-mode passive
[SwitchA] interface vlan-interface 10
[SwitchA-Vlan-interface10] isis bfd enable
[SwitchA-Vlan-interface10] bfd min-receive-interval 500
[SwitchA-Vlan-interface10] bfd min-transmit-interval 500
[SwitchA-Vlan-interface10] bfd detect-multiplier 7
# Enable BFD and configure BFD parameters on Switch B.
[SwitchB] bfd session init-mode active
[SwitchB] interface vlan-interface 10
[SwitchB-Vlan-interface10] isis bfd enable
[SwitchB-Vlan-interface10] bfd min-receive-interval 500
[SwitchB-Vlan-interface10] bfd min-transmit-interval 500
[SwitchB-Vlan-interface10] bfd detect-multiplier 8
[SwitchB-Vlan-interface10] return
Verifying the configuration
# Display the BFD session information on Switch A.
<SwitchA> display bfd session
Total Session Num: 1 Up Session Num: 1 Init Mode: Active
IPv4 Session Working Under Ctrl Mode:
LD/RD SourceAddr DestAddr State Holdtime Interface
3/1 192.168.0.102 192.168.0.100 Up 1700ms Vlan10
# Display routes destined for 120.1.1.1/32 on Switch A.
<SwitchA> display ip routing-table 120.1.1.1 verbose
Summary Count : 1
Destination: 120.1.1.1/32
Protocol: IS_L1
Process ID: 1
SubProtID: 0x1 Age: 04h20m37s
Cost: 10 Preference: 10
IpPre: N/A QosLocalID: N/A
Tag: 0 State: Active Adv
OrigTblID: 0x0 OrigVrf: default-vrf
TableID: 0x2 OrigAs: 0
NibID: 0x26000002 LastAs: 0
AttrID: 0xffffffff Neighbor: 0.0.0.0
Flags: 0x1008c OrigNextHop: 192.168.0.100
Label: NULL RealNextHop: 192.168.0.100
BkLabel: NULL BkNextHop: N/A
Tunnel ID: Invalid Interface: Vlan-interface10
BkTunnel ID: Invalid BkInterface: N/A
FtnIndex: 0x0 TrafficIndex: N/A
Connector: N/A
The output shows that Switch A and Switch B communicate through VLAN-interface 10. Then the link over VLAN-interface 10 fails.
# Display routes destined for 120.1.1.1/32 on Switch A.
<SwitchA> display ip routing-table 120.1.1.1 verbose
Summary Count : 1
Destination: 120.1.1.1/32
Protocol: IS_L1
Process ID: 1
SubProtID: 0x1 Age: 04h20m37s
Cost: 20 Preference: 10
IpPre: N/A QosLocalID: N/A
Tag: 0 State: Active Adv
OrigTblID: 0x0 OrigVrf: default-vrf
TableID: 0x2 OrigAs: 0
NibID: 0x26000002 LastAs: 0
AttrID: 0xffffffff Neighbor: 0.0.0.0
Flags: 0x1008c OrigNextHop: 10.1.1.100
Label: NULL RealNextHop: 10.1.1.100
BkLabel: NULL BkNextHop: N/A
Tunnel ID: Invalid Interface: Vlan-interface11
BkTunnel ID: Invalid BkInterface: N/A
FtnIndex: 0x0 TrafficIndex: N/A
Connector: N/A
The output shows that Switch A and Switch B communicate through VLAN-interface 11.
IS-IS FRR configuration example
Network requirements
As shown in Figure 49, Switch A, Switch B, and Switch C belong to the same IS-IS routing domain. Configure IS-IS FRR so that when the Link A fails, traffic can be switched to Link B immediately.
Table 15 Interface and IP address assignment
Device |
Interface |
IP address |
Device |
Interface |
IP address |
Switch A |
Vlan-int100 |
12.12.12.1/24 |
Switch B |
Vlan-int101 |
24.24.24.4/24 |
|
Vlan-int200 |
13.13.13.1/24 |
|
Vlan-int200 |
13.13.13.2/24 |
|
Loop0 |
1.1.1.1/32 |
|
Loop0 |
4.4.4.4/32 |
Switch C |
Vlan-int100 |
12.12.12.2/24 |
|
|
|
|
Vlan-int101 |
24.24.24.2/24 |
|
|
|
Configuration procedure
1. Configure IP addresses and subnet masks for interfaces on the switches. (Details not shown.)
2. Configure IS-IS on the switches to make sure Switch A, Switch B, and Switch C can communicate with each other at Layer 3. (Details not shown.)
3. Configure IS-IS FRR:
Enable IS-IS FRR to calculate a backup next hop through LFA calculation, or designate a backup next hop by using a referenced routing policy.
? (Method 1.) Enable IS-IS FRR to calculate a backup next hop through LFA calculation:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] isis 1
[SwitchA-isis-1] address-family ipv4
[SwitchA-isis-1-ipv4] fast-reroute lfa
[SwitchA-isis-1-ipv4] quit
[SwitchA-isis-1] quit
# Configure Switch B.
<SwitchB> system-view
[SwitchB] isis 1
[SwitchB-isis-1] address-family ipv4
[SwitchB-isis-1-ipv4] fast-reroute lfa
[SwitchB-isis-1-ipv4] quit
[SwitchB-isis-1] quit
? (Method 2.) Enable IS-IS FRR to designate a backup next hop by using a referenced routing policy:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] ip prefix-list abc index 10 permit 4.4.4.4 32
[SwitchA] route-policy frr permit node 10
[SwitchA-route-policy-frr-10] if-match ip address prefix-list abc
[SwitchA-route-policy-frr-10] apply fast-reroute backup-interface vlan-interface 100 backup-nexthop 12.12.12.2
[SwitchA-route-policy-frr-10] quit
[SwitchA] isis 1
[SwitchA-isis-1] address-family ipv4
[SwitchA-isis-1-ipv4] fast-reroute route-policy frr
[SwitchA-isis-1-ipv4] quit
[SwitchA-isis-1] quit
# Configure Switch B.
<SwitchB> system-view
[SwitchB] ip prefix-list abc index 10 permit 1.1.1.1 32
[SwitchB] route-policy frr permit node 10
[SwitchB-route-policy-frr-10] if-match ip address prefix-list abc
[SwitchB-route-policy-frr-10] apply fast-reroute backup-interface vlan-interface 101 backup-nexthop 24.24.24.2
[SwitchB-route-policy-frr-10] quit
[SwitchB] isis 1
[SwitchB-isis-1] address-family ipv4
[SwitchB-isis-1-ipv4] fast-reroute route-policy frr
[SwitchB-isis-1-ipv4] quit
[SwitchB-isis-1] quit
Verifying the configuration
# Display route 4.4.4.4/32 on Switch A to view the backup next hop information.
[SwitchA] display ip routing-table 4.4.4.4 verbose
Summary Count : 1
Destination: 4.4.4.4/32
Protocol: IS_L1
Process ID: 1
SubProtID: 0x1 Age: 04h20m37s
Cost: 10 Preference: 10
IpPre: N/A QosLocalID: N/A
Tag: 0 State: Active Adv
OrigTblID: 0x0 OrigVrf: default-vrf
TableID: 0x2 OrigAs: 0
NibID: 0x26000002 LastAs: 0
AttrID: 0xffffffff Neighbor: 0.0.0.0
Flags: 0x1008c OrigNextHop: 13.13.13.2
Label: NULL RealNextHop: 13.13.13.2
BkLabel: NULL BkNextHop: 12.12.12.2
Tunnel ID: Invalid Interface: Vlan-interface200
BkTunnel ID: Invalid BkInterface: Vlan-interface100
FtnIndex: 0x0 TrafficIndex: N/A
Connector: N/A
# Display route 1.1.1.1/32 on Switch B to view the backup next hop information.
[SwitchB] display ip routing-table 1.1.1.1 verbose
Summary Count : 1
Destination: 1.1.1.1/32
Protocol: IS_L1
Process ID: 1
SubProtID: 0x1 Age: 04h20m37s
Cost: 10 Preference: 10
IpPre: N/A QosLocalID: N/A
Tag: 0 State: Active Adv
OrigTblID: 0x0 OrigVrf: default-vrf
TableID: 0x2 OrigAs: 0
NibID: 0x26000002 LastAs: 0
AttrID: 0xffffffff Neighbor: 0.0.0.0
Flags: 0x1008c OrigNextHop: 13.13.13.1
Label: NULL RealNextHop: 13.13.13.1
BkLabel: NULL BkNextHop: 24.24.24.2
Tunnel ID: Invalid Interface: Vlan-interface200
BkTunnel ID: Invalid BkInterface: Vlan-interface101
FtnIndex: 0x0 TrafficIndex: N/A
Connector: N/A
Configuring BGP
Overview
Border Gateway Protocol (BGP) is an exterior gateway protocol (EGP). It is called internal BGP (IBGP) when it runs within an AS and called external BGP (EBGP) when it runs between ASs.
The current version in use is BGP-4 (RFC 4271).
BGP has the following characteristics:
· Focuses on route control and selection rather than route discovery and calculation.
· Uses TCP to enhance reliability.
· Measures the distance of a route by using a list of ASs that the route must travel through to reach the destination. BGP is also called a path-vector protocol.
· Supports CIDR.
· Reduces bandwidth consumption by advertising only incremental updates. BGP is very suitable to advertise large numbers of routes on the Internet.
· Eliminates routing loops by adding AS path information to BGP route updates.
· Uses policies to implement flexible route filtering and selection.
· Has good scalability.
BGP speaker and BGP peer
A router running BGP is a BGP speaker. A BGP speaker establishes peer relationships with other BGP speakers to exchange routing information over TCP connections.
BGP peers include the following types:
· IBGP peers—Reside in the same AS as the local router.
· EBGP peers—Reside in different ASs from the local router.
BGP message types
BGP uses the following message types:
· Open—After establishing a TCP connection, BGP sends an Open message to establish a session to the peer.
· Update—BGP sends update messages to exchange routing information between peers. Each update message can advertise a group of feasible routes with identical attributes and multiple withdrawn routes.
· Keepalive—BGP sends Keepalive messages between peers to maintain connectivity.
· Route-refresh—BGP sends a Route-refresh message to request the routing information for a specific address family from a peer.
· Notification—BGP sends a Notification message upon detecting an error and immediately closes the connection.
BGP path attributes
BGP uses the following path attributes in update messages for route filtering and selection:
· ORIGIN
The ORIGIN attribute specifies the origin of BGP routes. This attribute has the following types:
? IGP—Has the highest priority. Routes generated in the local AS have the IGP attribute.
? EGP—Has the second highest priority. Routes obtained through EGP have the EGP attribute.
? INCOMPLETE—Has the lowest priority. The source of routes with this attribute is unknown. Routes redistributed from other routing protocols have the INCOMPLETE attribute.
· AS_PATH
The AS_PATH attribute identifies the ASs through which a route has passed. Before advertising a route to another AS, BGP adds the local AS number into the AS_PATH attribute, so the receiver can determine ASs to route the message back.
The AS_PATH attribute has the following types:
? AS_SEQUENCE—Arranges AS numbers in sequence. As shown in Figure 50, the number of the AS closest to the receiver's AS is leftmost.
? AS_SET—Arranges AS numbers randomly.
Figure 50 AS_PATH attribute
BGP uses the AS_PATH attribute to implement the following functions:
? Avoid routing loops—A BGP router does not receive routes containing the local AS number to avoid routing loops.
? Affect route selection—BGP gives priority to the route with the shortest AS_PATH length if other factors are the same. As shown in Figure 50, the BGP router in AS 50 gives priority to the route passing AS 40 for sending data to the destination 8.0.0.0. In some applications, you can apply a routing policy to control BGP route selection by modifying the AS_PATH length. For more information about routing policy, see "Configuring routing policies."
? Filter routes—By using an AS path list, you can filter routes based on AS numbers contained in the AS_PATH attribute. For more information about AS path list, see "Configuring routing policies."
· NEXT_HOP
The NEXT_HOP attribute may not be the IP address of a directly connected router. Its value is determined as follows:
? When a BGP speaker advertises a self-originated route to a BGP peer, it sets the address of the sending interface as the NEXT_HOP.
? When a BGP speaker sends a received route to an EBGP peer, it sets the address of the sending interface as the NEXT_HOP.
? When a BGP speaker sends a route received from an EBGP peer to an IBGP peer, it does not modify the NEXT_HOP attribute. If load balancing is configured, BGP modifies the NEXT_HOP attribute for the equal-cost routes. For load balancing information, see "BGP load balancing."
· MED (MULTI_EXIT_DISC)
BGP advertises the MED attribute between two neighboring ASs, each of which does not advertise the attribute to any other AS.
Similar to metrics used by IGPs, MED is used to determine the optimal route for traffic going into an AS. When a BGP router obtains multiple routes to the same destination but with different next hops, it considers the route with the smallest MED value as the optimal route. As shown in Figure 52, traffic from AS 10 to AS 20 travels through Router B that is selected according to MED.
Figure 52 MED attribute
Generally BGP only compares MEDs of routes received from the same AS. You can also use the compare-different-as-med command to force BGP to compare MED values of routes received from different ASs.
· LOCAL_PREF
The LOCAL_PREF attribute is exchanged between IBGP peers only, and is not advertised to any other AS. It indicates the priority of a BGP router.
BGP uses LOCAL_PREF to determine the optimal route for traffic leaving the local AS. When a BGP router obtains multiple routes to the same destination but with different next hops, it considers the route with the highest LOCAL_PREF value as the optimal route. As shown in Figure 53, traffic from AS 20 to AS 10 travels through Router C that is selected according to LOCAL_PREF.
Figure 53 LOCAL_PREF attribute
· COMMUNITY
The COMMUNITY attribute identifies the community of BGP routes. A BGP community is a group of routes with the same characteristics. It has no geographical boundaries. Routes of different ASs can belong to the same community.
A route can carry one or more COMMUNITY attribute values (each of which is represented by a 4-byte integer). A router uses the COMMUNITY attribute to determine whether to advertise the route and the advertising scope without using complex filters such as ACLs. This mechanism simplifies routing policy configuration, management, and maintenance.
Well-known COMMUNITY attributes involve the following:
? INTERNET—By default, all routes belong to the Internet community. Routes with this attribute can be advertised to all BGP peers.
? NO_EXPORT—Routes with this attribute cannot be advertised out of the local AS or out of the local confederation, but can be advertised to other sub-ASs in the confederation. For confederation information, see "Settlements for problems in large-scale BGP networks."
? No_ADVERTISE—Routes with this attribute cannot be advertised to other BGP peers.
? No_EXPORT_SUBCONFED—Routes with this attribute cannot be advertised out of the local AS or other sub-ASs in the local confederation.
You can configure BGP community lists to filter BGP routes based on the BGP COMMUNITY attribute.
· Extended community attribute
To meet new demands, BGP defines the extended community attribute. The extended community attribute has the following advantages over the COMMUNITY attribute:
? Provides more attribute values by extending the attribute length to eight bytes.
? Allows for using different types of extended community attributes in different scenarios to enhance route filtering and control and simplify configuration and management.
The device supports the route target and Site of Origin (SoO) extended community attributes. For information about route target, see MPLS Configuration Guide.
The SoO attribute specifies the site where the route originated. It prevents advertising a route back to the originating site. If the AS-path attribute is lost, the router can use the SoO attribute to avoid routing loops.
The SoO attribute has the following formats:
? 16-bit AS number:32-bit user-defined number. For example, 100:3.
? 32-bit IP address:16-bit user-defined number. For example, 192.168.122.15:1.
? 32-bit AS number:16-bit user-defined number, where the minimum value of the AS number is 65536. For example, 65536:1.
BGP route selection
BGP discards routes with unreachable NEXT_HOPs. If multiple routes to the same destination are available, BGP selects the optimal route in the following sequence:
1. The route with the highest Preferred_value.
2. The route with the highest LOCAL_PREF.
3. The route generated by the network command, the route redistributed by the import-route command, or the summary route in turn.
4. The route with the shortest AS_PATH.
5. The IGP, EGP, or INCOMPLETE route in turn.
6. The route with the lowest MED value.
7. The route learned from EBGP, confederation EBGP, confederation IBGP, or IBGP in turn.
8. The route with the smallest IGP metric.
9. The route with the smallest recursion depth.
10. If all routes are received from EBGP peers and the peers have different router IDs, the route that used to be an optimal route becomes the optimal route.
11. The route advertised by the router with the smallest router ID.
If one of the routes is advertised by a route reflector, BGP compares the ORIGINATOR_ID of the route with the router IDs of other routers. Then, BGP selects the route with the smallest ID as the optimal route.
12. The route with the shortest CLUSTER_LIST.
13. The route advertised by the peer with the lowest IP address.
The CLUSTER_IDs of route reflectors form a CLUSTER_LIST. If a route reflector receives a route that contains its own CLUSTER ID in the CLUSTER_LIST, the router discards the route to avoid routing loops.
If load balancing is configured, the system selects available routes to implement load balancing.
BGP route advertisement rules
BGP follows these rules for route advertisement:
· When multiple feasible routes to a destination exist, BGP advertises only the optimal route to its peers. If the advertise-rib-active command is configured, BGP advertises the optimal route in the IP routing table. If not, BGP advertises the optimal route in the BGP routing table.
· BGP advertises only routes that it uses.
· BGP advertises routes learned from an EBGP peer to all BGP peers, including both EBGP and IBGP peers.
· BGP advertises routes learned from an IBGP peer to EBGP peers, rather than other IBGP peers.
· After establishing a session to a new BGP peer, BGP advertises all the routes matching the above rules to the peer. After that, BGP advertises only incremental updates to the peer.
BGP load balancing
BGP load balancing is applicable between EBGP peers, between IBGP peers, and between confederations.
BGP implements load balancing through route recursion and route selection.
BGP load balancing through route recursion
The next hop of a BGP route might not be directly connected. One of the reasons is that the next hop information exchanged between IBGP peers is not modified. The BGP router must find the directly connected next hop through IGP. The matching route with the direct next hop is called the recursive route. The process of finding a recursive route is route recursion.
If multiple recursive routes to the same destination are load balanced, BGP generates the same number of next hops to forward packets.
BGP load balancing based on route recursion is always enabled in the system.
BGP load balancing through route selection
IGP routing protocols, such as RIP and OSPF, can use route metrics as criteria to load balance between routes that have the same metric. BGP cannot load balance between routes by route metrics as an IGP protocol does, because BGP does not have a route computation algorithm.
BGP uses the following load balancing criteria to determine load balanced routes:
· The routes have the same ORIGIN, LOCAL_PREF, and MED attributes. If the balance as-path-neglect command is not configured, the routes must also have the same AS_PATH attribute.
· The routes have the same MPLS label assignment status (labeled or not labeled).
BGP does not use the route selection rules described in "BGP route selection" for load balancing.
As shown in Figure 54, Router A and Router B are IBGP peers of Router C. Router C allows a maximum number of two ECMP routes for load balancing.
Router D and Router E both advertise a route 9.0.0.0 to Router C. Router C installs the two routes to its routing table for load balancing if the routes meet the BGP load balancing criteria. After that, Router C forwards to Router A and Router B a single route whose attributes are changed as follows:
· AS_PATH attribute:
? If the balance as-path-neglect command is not configured, the AS_PATH attribute does not change.
? If the balance as-path-neglect command is configured, the AS_PATH attribute is changed to the attribute of the optimal route.
· The NEXT_HOP attribute is changed to the IP address of Router C.
· Other attributes are changed to be the same as the optimal route.
Settlements for problems in large-scale BGP networks
You can use the following methods to facilitate management and improve route distribution efficiency on a large-scale BGP network.
· Route summarization
Route summarization can reduce the BGP routing table size by advertising summary routes rather than more specific routes.
The system supports both manual and automatic route summarization. Manual route summarization allows you to determine the attribute of a summary route and whether to advertise more specific routes.
· Route dampening
Route flapping (a route comes up and disappears in the routing table frequently) causes BGP to send many routing updates. It can consume too many resources and affect other operations.
In most cases, BGP runs in complex networks where route changes are more frequent. To solve the problem caused by route flapping, you can use BGP route dampening to suppress unstable routes.
BGP route dampening uses a penalty value to judge the stability of a route. The bigger the value, the less stable the route. Each time a route state changes from reachable to unreachable, or a reachable route's attribute changes, BGP adds a penalty value of 1000 to the route. When the penalty value of the route exceeds the suppress value, the route is suppressed and cannot become the optimal route. When the penalty value reaches the upper limit, no penalty value is added.
If the suppressed route does not flap, its penalty value gradually decreases to half of the suppress value after a period of time. This period is called "Half-life." When the value decreases to the reusable threshold value, the route is usable again.
Figure 55 BGP route dampening
· Peer group
You can organize BGP peers with the same attributes into a group to simplify their configurations.
When a peer joins the peer group, the peer obtains the same configuration as the peer group. If the configuration of the peer group is changed, the configuration of group members is changed.
· Community
You can apply a community list or an extended community list to a routing policy for route control. For more information, see "BGP path attributes."
· Route reflector
IBGP peers must be fully meshed to maintain connectivity. If n routers exist in an AS, the number of IBGP connections is n(n-1)/2. If a large number of IBGP peers exist, large amounts of network and CPU resources are consumed to maintain sessions.
Using route reflectors can solve this issue. In an AS, a router acts as a route reflector, and other routers act as clients connecting to the route reflector. The route reflector forwards routing information received from a client to other clients. In this way, all clients can receive routing information from one another without establishing BGP sessions.
A router that is neither a route reflector nor a client is a non-client, which, as shown in Figure 56, must establish BGP sessions to the route reflector and other non-clients.
Figure 56 Network diagram for a route reflector
The route reflector and clients form a cluster. Typically a cluster has one route reflector. The ID of the route reflector is the Cluster_ID. You can configure more than one route reflector in a cluster to improve availability, as shown in Figure 57. The configured route reflectors must have the same Cluster_ID to avoid routing loops.
Figure 57 Network diagram for route reflectors
When the BGP routers in an AS are fully meshed, route reflection is unnecessary because it consumes more bandwidth resources. You can use commands to disable route reflection instead of modifying network configuration or changing network topology.
After route reflection is disabled between clients, routes can still be reflected between a client and a non-client.
· Confederation
Confederation is another method to manage growing IBGP connections in an AS. It splits an AS into multiple sub-ASs. In each sub-AS, IBGP peers are fully meshed. As shown in Figure 58, intra-confederation EBGP connections are established between sub-ASs in AS 200.
Figure 58 Confederation network diagram
A non-confederation BGP speaker does not need to know sub-ASs in the confederation. It considers the confederation as one AS, and the confederation ID as the AS number. In the above figure, AS 200 is the confederation ID.
Confederation has a deficiency. When you change an AS into a confederation, you must reconfigure the routers, and the topology will be changed.
In large-scale BGP networks, you can use both route reflector and confederation.
MP-BGP
BGP-4 can only advertise IPv4 unicast routing information. Multiprotocol Extensions for BGP-4 (MP-BGP) can advertise routing information for the following address families:
· IPv6 unicast address family.
· IPv4 multicast address family.
PIM uses static and dynamic unicast routes to perform RPF check before creating multicast routing entries. When the multicast and unicast topologies are different, you can use MP-BGP to advertise the routes for RPF check. MP-BGP stores the routes in the BGP multicast routing table. For more information about PIM and RPF check, see IP Multicast Configuration Guide.
· VPNv4 and VPNv6 address families.
For more information about VPNv4 and VPNv6, see MPLS Configuration Guide.
· Labeled IPv4 unicast and IPv6 unicast address families.
MP-BGP advertises IPv4 unicast/IPv6 unicast routes and MPLS labels assigned for the routes. Labeled IPv4 unicast routes apply to inter-AS Option C for MPLS L3VPN. Labeled IPv6 unicast routes apply to 6PE and inter-AS Option C for MPLS L3VPN. For more information about inter-AS Option C, see MPLS Configuration Guide.
· EVPN address family.
MP-BGP advertises EVPN routes to implement automatic VTEP discovery, VXLAN tunnel establishment and assignment, and MAC and ARP information advertisement. For more information about EVPN, see EVPN Configuration Guide.
MP-BGP extended attributes
Prefixes and next hops are key routing information. BGP-4 uses update messages to carry the following information:
· Feasible route prefixes in the Network Layer Reachability Information (NLRI) field.
· Unfeasible route prefixes in the withdrawn routes field.
· Next hops in the NEXT_HOP attribute.
BGP-4 cannot carry routing information for multiple network layer protocols.
To support multiple network layer protocols, MP-BGP defines the following path attributes:
· MP_REACH_NLRI—Carries feasible route prefixes and next hops for multiple network layer protocols.
· MP_UNREACH_NLRI—Carries unfeasible route prefixes for multiple network layer protocols.
MP-BGP uses these two attributes to advertise feasible and unfeasible routes for different network layer protocols. BGP speakers not supporting MP-BGP ignore updates containing these attributes and do not forward them to its peers.
Address family
MP-BGP uses address families and subsequent address families to identify different network layer protocols for routes contained in the MP_REACH_NLRI and MP_UNREACH_NLRI attributes. For example, an Address Family Identifier (AFI) of 2 and a Subsequent Address Family Identifier (SAFI) of 1 identify IPv6 unicast routing information carried in the MP_REACH_NLRI attribute. For address family values, see RFC 1700.
BGP multi-instance
A BGP router can run multiple BGP processes. Each BGP process corresponds to a BGP instance. BGP maintains an independent routing table for each BGP instance. You can enable session multithreading for each BGP process. The session multithreading feature implements the parallel processing of sessions for different BGP peers on different threads.
You can create multiple public address families for a BGP instance. However, each public address family (except for public VPNv4 and VPNv6 address families) can belong to only one BGP instance.
You can create multiple VPN instances for a BGP instance, and each VPN instance can have multiple address families. A VPN instance can belong to only one BGP instance.
Different BGP instances can have the same AS number but cannot have the same name.
BGP configuration views
BGP uses different views to manage routing information for different BGP instances, address families, and VPN instances. Most BGP commands are available in all BGP views. BGP supports multiple VPN instances by establishing a separate routing table for each VPN instance.
Table 16 describes different BGP configuration views.
Table 16 BGP configuration views
View names |
Ways to enter the views |
Remarks |
BGP instance view |
You can create a BGP instance and enter its view by specifying the instance keyword in the bgp command. Configurations in this view apply to all public address families for the specified BGP instance and all VPN instances (such as confederation, GR, and logging configurations), or apply to all public address families for the specified BGP instance. |
|
BGP IPv4 unicast address family view |
Configurations in this view apply to public IPv4 unicast routes and peers of the specified BGP instance. |
|
BGP IPv6 unicast address family view |
Configurations in this view apply to public IPv6 unicast routes and peers of the specified BGP instance. |
|
BGP IPv4 multicast address family view |
Configurations in this view apply to IPv4 multicast routes and peers of the specified BGP instance. |
|
BGP VPNv4 address family view |
Configurations in this view apply to VPNv4 routes and peers of the specified BGP instance. For more information about BGP VPNv4 address family view, see MPLS Configuration Guide. |
|
BGP VPNv6 address family view |
Configurations in this view apply to VPNv6 routes and peers of the specified BGP instance. For more information about BGP VPNv6 address family view, see MPLS Configuration Guide. |
|
BGP EVPN address family view |
Configurations in this view apply to EVPN routes and peers of the specified BGP instance. For more information about BGP EVPN address family view, see EVPN Configuration Guide. |
|
BGP-VPN instance view |
Configurations in this view apply to all address families in the specified VPN instance of the specified BGP instance. |
|
BGP-VPN IPv4 unicast address family view |
Configurations in this view apply to IPv4 unicast routes and peers in the specified VPN instance of the specified BGP instance. |
|
BGP-VPN IPv6 unicast address family view |
Configurations in this view apply to IPv6 unicast routes and peers in the specified VPN instance of the specified BGP instance. |
|
BGP-VPN VPNv4 address family view |
Configurations in this view apply to VPNv4 routes and peers in the specified VPN instance of the specified BGP instance. For more information about BGP-VPN VPNv4 address family view, see MPLS Configuration Guide. |
|
BGP LS address family view |
Configurations in this view apply to LS messages and peers of the specified BGP instance. |
Protocols and standards
· RFC 1700, ASSIGNED NUMBERS
· RFC 1771, A Border Gateway Protocol 4 (BGP-4)
· RFC 1997, BGP Communities Attribute
· RFC 2439, BGP Route Flap Damping
· RFC 2796, BGP Route Reflection
· RFC 2858, Multiprotocol Extensions for BGP-4
· RFC 2918, Route Refresh Capability for BGP-4
· RFC 3065, Autonomous System Confederations for BGP
· RFC 3392, Capabilities Advertisement with BGP-4
· RFC 4271, A Border Gateway Protocol 4 (BGP-4)
· RFC 4360, BGP Extended Communities Attribute
· RFC 4724, Graceful Restart Mechanism for BGP
· RFC 4760, Multiprotocol Extensions for BGP-4
· RFC 5082, The Generalized TTL Security Mechanism (GTSM)
· RFC 6037, Cisco Systems' Solution for Multicast in BGP MPLS IP VPNs
BGP configuration task list
On a basic BGP network, perform the following configuration tasks:
· Enable BGP.
· Configure BGP peers or peer groups. If you configure a BGP setting at both the peer group and the peer level, the most recent configuration takes effect on the peer.
· Control BGP route generation.
To control BGP route distribution and path selection, you must perform additional configuration tasks.
To configure BGP, perform the following tasks (IPv4 unicast/IPv4 multicast):
To configure BGP, perform the following tasks (IPv6 unicast):
Configuring basic BGP
This section describes the basic settings required for a BGP network to run.
Enabling BGP
A router ID is the unique identifier of a BGP router in an AS.
· To ensure the uniqueness of a router ID and enhance availability, specify in BGP instance view the IP address of a local loopback interface as the router ID. Different BGP instances can have the same router ID.
· If no router ID is specified in BGP instance view, the global router ID is used.
· To modify a non-zero router ID of a BGP instance , use the router-id command in BGP instance view, rather than the router id command in system view.
· If you specify a router ID in BGP instance view and then remove the interface that owns the router ID, the router does not select a new router ID. To select a new router ID, use the undo router-id command in BGP instance view.
To enable BGP:
Step |
Command |
Remarks |
|
1. Enter system view. |
system-view |
N/A |
|
2. Configure a global router ID. |
router id router-id |
By default, no global router ID is configured, and BGP uses the highest loopback interface IP address—if any—as the router ID. If no loopback interface IP address is available, BGP uses the highest physical interface IP address as the route ID regardless of the interface status. |
|
3. Enable BGP and enter BGP instance view. |
bgp as-number [ instance instance-name ] [ multi-session-thread ] |
By default, BGP is disabled and no BGP instances exist. |
|
4. (Optional.) Configure an SNMP context for the BGP instance. |
snmp context-name context-name |
By default, no SNMP context is configured for a BGP instance. |
|
5. (Optional.) Configure a router ID for the BGP instance. |
router-id router-id |
By default, no router ID is configured for a BGP instance, and the BGP instance uses the global router ID configured by the router-id command in system view. |
|
6. (Optional.) Enter BGP-VPN instance view. |
ip vpn-instance vpn-instance-name |
The specified VPN instance must have been created and have an RD. For more information about VPN instances, see MPLS Configuration Guide. |
|
7. (Optional.) Configure a router ID for the BGP VPN instance. |
router-id { router-id | auto-select } |
By default, no router ID is configured for a BGP VPN instance, and the BGP VPN instance uses the router ID configured in BGP instance view. If no router ID is configured in BGP instance view, the BGP VPN instance uses the global router ID configured in system view. |
|
Configuring a BGP peer
Configuring a BGP peer (IPv4 unicast address family)
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Create an IPv4 BGP peer and specify its AS number. |
peer ipv4-address as-number as-number |
By default, no IPv4 BGP peers exist. |
4. (Optional.) Configure a description for a peer. |
peer ipv4-address description text |
By default, no description is configured for a peer. |
5. Create the BGP IPv4 unicast address family or BGP-VPN IPv4 unicast address family and enter its view. |
address-family ipv4 [ unicast ] |
By default, no BGP IPv4 unicast address family or BGP-VPN IPv4 unicast address family exists. |
6. Enable the router to exchange IPv4 unicast routing information with the specified peer. |
peer ipv4-address enable |
By default, the router cannot exchange IPv4 unicast routing information with the peer. |
Configuring a BGP peer (IPv6 unicast address family)
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Create an IPv6 BGP peer and specify its AS number. |
peer ipv6-address as-number as-number |
By default, no IPv6 BGP peers exist. |
4. (Optional.) Configure a description for a peer. |
peer ipv6-address description text |
By default, no description is configured for a peer. |
5. Create the BGP IPv6 unicast address family or BGP-VPN IPv6 unicast address family and enter its view. |
address-family ipv6 [ unicast ] |
By default, no BGP IPv6 unicast address family or BGP-VPN IPv6 unicast address family exists. |
6. Enable the router to exchange IPv6 unicast routing information with the specified peer. |
peer ipv6-address enable |
By default, the router cannot exchange IPv6 unicast routing information with the peer. |
Configuring a BGP peer (IPv4 multicast address family)
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view |
bgp as-number [ instance instance-name ] [ multi-session-thread ] |
N/A |
3. Create an IPv4 BGP peer and specify its AS number. |
peer ipv4-address as-number as-number |
By default, no IPv4 BGP peers exist. |
4. (Optional.) Configure a description for the peer. |
peer ipv4-address description text |
By default, no description is configured for a peer. |
5. Create the BGP IPv4 multicast address family and enter its view. |
address-family ipv4 multicast |
By default, no BGP IPv4 multicast address family exists. |
6. Enable the router to exchange IPv4 unicast routing information used for RPF check with the specified peer. |
peer ipv4-address enable |
By default, the router cannot exchange IPv4 unicast routing information used for RPF check with the peer. |
Configuring dynamic BGP peers
This feature enables BGP to establish dynamic BGP peer relationships with devices in a network. BGP accepts connection requests from the network but it does not initiate connection requests to the network.
After a device in the network initiates a connection request, BGP establishes a dynamic peer relationship with the device.
If multiple BGP peers reside in the same network, you can use this feature to simplify BGP peer configuration.
Configuring dynamic BGP peers (IPv4 unicast address family)
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Specify devices in a network as dynamic BGP peers and specify an AS number for the peers. |
peer ipv4-address mask-length as-number as-number |
By default, no dynamic BGP peers exist. |
4. (Optional.) Configure a description for dynamic BGP peers. |
peer ipv4-address mask-length description text |
By default, no description is configured for dynamic BGP peers. |
5. Create the BGP IPv4 unicast address family or BGP-VPN IPv4 unicast address family and enter its view. |
address-family ipv4 [ unicast ] |
By default, no BGP IPv4 unicast address family or BGP-VPN IPv4 unicast address family exists. |
6. Enable BGP to exchange IPv4 unicast routing information with dynamic BGP peers in the specified network. |
peer ipv4-address mask-length enable |
By default, BGP cannot exchange IPv4 unicast routing information with dynamic BGP peers. |
Configuring dynamic BGP peers (IPv6 unicast address family)
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Specify devices in a network as dynamic BGP peers and specify an AS number for the peers. |
peer ipv6-address prefix-length as-number as-number |
By default, no dynamic BGP peers exist. |
4. (Optional.) Configure a description for dynamic BGP peers. |
peer ipv6-address prefix-length description text |
By default, no description is configured for dynamic BGP peers. |
5. Create the BGP IPv6 unicast address family or BGP-VPN IPv6 unicast address family and enter its view. |
address-family ipv6 [ unicast ] |
By default, no BGP IPv6 unicast address family or BGP-VPN IPv6 unicast address family exists. |
6. Enable BGP to exchange IPv6 unicast routing information with dynamic BGP peers in the specified network. |
peer ipv6-address prefix-length enable |
By default, BGP cannot exchange IPv6 unicast routing information with dynamic BGP peers. |
Configuring dynamic BGP peers (IPv4 multicast address family)
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view. |
bgp as-number [ instance instance-name ] [ multi-session-thread ] |
N/A |
3. Specify devices in a network as dynamic BGP peers and specify an AS number for the peers. |
peer ipv4-address mask-length as-number as-number |
By default, no dynamic BGP peers exist. |
4. (Optional.) Configure a description for dynamic BGP peers. |
peer ipv4-address mask-length description text |
By default, no description is configured for dynamic BGP peers. |
5. Create the BGP IPv4 multicast address family and enter its view. |
address-family ipv4 multicast |
By default, no BGP IPv4 multicast address family exists. |
6. Enable BGP to exchange IPv4 unicast routing information used for RPF check with dynamic BGP peers in the specified network. |
peer ipv4-address mask-length enable |
By default, BGP cannot exchange IPv4 unicast routing information used for RPF check with dynamic BGP peers. |
Configuring a BGP peer group
The peers in a peer group use the same route selection policy.
In a large-scale network, many peers can use the same route selection policy. You can configure a peer group and add these peers into this group. When you change the policy for the group, the modification also applies to the peers in the group.
A peer group is an IBGP peer group if peers in it belong to the local AS, and is an EBGP peer group if peers in it belong to different ASs.
Configuring an IBGP peer group
After you create an IBGP peer group and then add a peer into it, the system creates the peer in BGP instance view and specifies the local AS number for the peer.
To configure an IBGP peer group (IPv4 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Create an IBGP peer group. |
group group-name [ internal ] |
By default, no IBGP peer groups exist. |
4. Add a peer into the IBGP peer group. |
peer ipv4-address [ mask-length ] group group-name [ as-number as-number ] |
By default, no peer exists in the peer group. The as-number as-number option must specify the local AS number. |
5. (Optional.) Configure a description for the peer group. |
peer group-name description text |
By default, no description is configured for the peer group. |
6. Create the BGP IPv4 unicast address family or BGP-VPN IPv4 unicast address family and enter its view. |
address-family ipv4 [ unicast ] |
By default, no BGP IPv4 unicast address family or BGP-VPN IPv4 unicast address family exists. |
7. Enable the router to exchange IPv4 unicast routing information with peers in the specified peer group. |
peer group-name enable |
By default, the router cannot exchange IPv4 unicast routing information with the peers. |
To configure an IBGP peer group (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Create an IBGP peer group. |
group group-name [ internal ] |
By default, no IBGP peer groups exist. |
4. Add a peer into the IBGP peer group. |
peer ipv6-address [ prefix-length ] group group-name [ as-number as-number ] |
By default, no peer exists in the peer group. The as-number as-number option must specify the local AS number. |
5. (Optional.) Configure a description for the peer group. |
peer group-name description text |
By default, no description is configured for the peer group. |
6. Create the BGP IPv6 unicast address family or BGP-VPN IPv6 unicast address family and enter its view. |
address-family ipv6 [ unicast ] |
By default, no BGP IPv6 unicast address family or BGP-VPN IPv6 unicast address family exists. |
7. Enable the router to exchange IPv6 unicast routing information with peers in the specified peer group. |
peer group-name enable |
By default, the router cannot exchange IPv6 unicast routing information with the peers. |
To configure an IBGP peer group (IPv4 multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view. |
bgp as-number [ instance instance-name ] [ multi-session-thread ] |
N/A |
3. Create an IBGP peer group. |
group group-name [ internal ] |
By default, no IBGP peer groups exist. |
4. Add an IPv4 peer into the IBGP peer group. |
peer ipv4-address [ mask-length ] group group-name [ as-number as-number ] |
By default, no peer exists in the peer group. The as-number as-number option must specify the local AS number. |
5. (Optional.) Configure a description for the peer group. |
peer group-name description text |
By default, no description is configured for the peer group. |
6. Create the BGP IPv4 multicast address family and enter its view. |
address-family ipv4 multicast |
By default, no BGP IPv4 multicast address family exists. |
7. Enable the router to exchange IPv4 unicast routing information used for RPF check with peers in the specified peer group. |
peer group-name enable |
By default, the router cannot exchange IPv4 unicast routing information used for RPF check with the peers in the peer group. |
Configuring an EBGP peer group
If peers in an EBGP group belong to the same external AS, the EBGP peer group is a pure EBGP peer group. If not, it is a mixed EBGP peer group.
Use one of the following methods to configure an EBGP peer group:
· Method 1—Create an EBGP peer group, specify its AS number, and add peers into it. All the added peers have the same AS number. All peers in the peer group have the same AS number as the peer group. You can specify an AS number for a peer before adding it into the peer group. The AS number must be the same as that of the peer group.
· Method 2—Create an EBGP peer group, specify an AS number for a peer, and add the peer into the peer group. Peers added in the group can have different AS numbers.
· Method 3—Create an EBGP peer group and add a peer with an AS number into it. Peers added in the group can have different AS numbers.
To configure an EBGP peer group by using Method 1 (IPv4 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Create an EBGP peer group. |
group group-name external |
By default, no EBGP peer groups exist. |
4. Specify the AS number of the group. |
peer group-name as-number as-number |
By default, no AS number is specified. If a peer group contains peers, you cannot remove or change its AS number. |
5. Add a peer into the EBGP peer group. |
peer ipv4-address [ mask-length ] group group-name [ as-number as-number ] |
By default, no peers exist in the peer group. The as-number as-number option, if used, must specify the same AS number as the peer group-name as-number as-number command. |
6. (Optional.) Configure a description for the peer group. |
peer group-name description text |
By default, no description is configured for the peer group. |
7. Create the BGP IPv4 unicast address family or BGP-VPN IPv4 unicast address family and enter its view. |
address-family ipv4 [ unicast ] |
By default, no BGP IPv4 unicast address family or BGP-VPN IPv4 unicast address family exists. |
8. Enable the router to exchange IPv4 unicast routing information with peers in the specified peer group. |
peer group-name enable |
By default, the router cannot exchange IPv4 unicast routing information with the peers. |
To configure an EBGP peer group by using Method 1 (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Create an EBGP peer group. |
group group-name external |
By default, no EBGP peer groups exist. |
4. Specify the AS number of the group. |
peer group-name as-number as-number |
By default, no AS number is specified. If a peer group contains peers, you cannot remove or change its AS number. |
5. Add a peer into the EBGP peer group. |
peer ipv6-address [ prefix-length ] group group-name [ as-number as-number ] |
By default, no peers exist in the peer group. The as-number as-number option, if used, must specify the same AS number as the peer group-name as-number as-number command. |
6. (Optional.) Configure a description for the peer group. |
peer group-name description text |
By default, no description is configured for the peer group. |
7. Create the BGP IPv6 unicast address family or BGP-VPN IPv6 unicast address family and enter its view. |
address-family ipv6 [ unicast ] |
By default, no BGP IPv6 unicast address family or BGP-VPN IPv6 unicast address family exists. |
8. Enable the router to exchange IPv6 unicast routing information with peers in the specified peer group. |
peer group-name enable |
By default, the router cannot exchange IPv6 unicast routing information with the peers. |
To configure an EBGP peer group by using Method 1 (IPv4 multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view. |
bgp as-number [ instance instance-name ] [ multi-session-thread ] |
N/A |
3. Create an EBGP peer group. |
group group-name external |
By default, no EBGP peer groups exist. |
4. Specify the AS number of the group. |
peer group-name as-number as-number |
By default, no AS number is specified. If a peer group contains peers, you cannot remove or change its AS number. |
5. Add an IPv4 BGP peer into the EBGP peer group. |
peer ipv4-address [ mask-length ] group group-name [ as-number as-number ] |
By default, no peers exist in the peer group. The as-number as-number option, if used, must specify the same AS number as the peer group-name as-number as-number command. |
6. (Optional.) Configure a description for the peer group. |
peer group-name description text |
By default, no description is configured for the peer group. |
7. Create the BGP IPv4 multicast address family and enter its view. |
address-family ipv4 multicast |
By default, no BGP IPv4 multicast address family exists. |
8. Enable the router to exchange IPv4 unicast routing information used for RPF check with peers in the specified peer group. |
peer group-name enable |
By default, the router cannot exchange IPv4 unicast routing information used for RPF check with the peers in the group. |
To configure an EBGP peer group by using Method 2 (IPv4 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Create an EBGP peer group. |
group group-name external |
By default, no EBGP peer groups exist. |
4. Create an IPv4 BGP peer and specify its AS number. |
peer ipv4-address [ mask-length ] as-number as-number |
By default, no IPv4 BGP peers exist. |
5. Add the peer into the EBGP peer group. |
peer ipv4-address [ mask-length ] group group-name [ as-number as-number ] |
By default, no peers exist in the peer group. The as-number as-number option, if used, must specify the same AS number as the peer ipv4-address [ mask-length ] as-number as-number command. |
6. (Optional.) Configure a description for the peer group. |
peer group-name description text |
By default, no description is configured for the peer group. |
7. Create the BGP IPv4 unicast address family or BGP-VPN IPv4 unicast address family and enter its view. |
address-family ipv4 [ unicast ] |
By default, no BGP IPv4 unicast address family or BGP-VPN IPv4 unicast address family exists. |
8. Enable the router to exchange IPv4 unicast routing information with peers in the specified peer group. |
peer group-name enable |
By default, the router cannot exchange IPv4 unicast routing information with the peers. |
To configure an EBGP peer group by using Method 2 (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Create an EBGP peer group. |
group group-name external |
By default, no EBGP peer groups exist. |
4. Create an IPv6 BGP peer and specify its AS number. |
peer ipv6-address [ prefix-length ] as-number as-number |
By default, no IPv6 BGP peers exist. |
5. Add the peer into the EBGP peer group. |
peer ipv6-address [ prefix-length ] group group-name [ as-number as-number ] |
By default, no peers exist in the peer group. The as-number as-number option, if used, must specify the same AS number as the peer ipv4-address [ prefix-length ] as-number as-number command. |
6. (Optional.) Configure a description for the peer group. |
peer group-name description text |
By default, no description is configured for the peer group. |
7. Create the BGP IPv6 unicast address family or BGP-VPN IPv6 unicast address family and enter its view. |
address-family ipv6 [ unicast ] |
By default, no BGP IPv6 unicast address family or BGP-VPN IPv6 unicast address family exists. |
8. Enable the router to exchange IPv6 unicast routing information with peers in the specified peer group. |
peer group-name enable |
By default, the router cannot exchange IPv6 unicast routing information with the peers. |
To configure an EBGP peer group by using Method 2 (IPv4 multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view. |
bgp as-number [ instance instance-name ] [ multi-session-thread ] |
N/A |
3. Create an EBGP peer group. |
group group-name external |
By default, no EBGP peer groups exist. |
4. Create an IPv4 BGP peer and specify its AS number. |
peer ipv4-address [ mask-length ] as-number as-number |
By default, no IPv4 BGP peers exist. |
5. Add the peer into the EBGP peer group. |
peer ipv4-address [ mask-length ] group group-name [ as-number as-number ] |
By default, no peers exist in the peer group. The as-number as-number option, if used, must specify the same AS number as the peer ipv4-address [ mask-length ] as-number as-number command. |
6. (Optional.) Configure a description for the peer group. |
peer group-name description text |
By default, no description is configured for the peer group. |
7. Create the BGP IPv4 multicast address family and enter its view. |
address-family ipv4 multicast |
By default, no BGP IPv4 multicast address family exists. |
8. Enable the router to exchange IPv4 unicast routing information used for RPF check with peers in the specified peer group. |
peer group-name enable |
By default, the router cannot exchange IPv4 unicast routing information used for RPF check with the peers in the group. |
To configure an EBGP peer group by using Method 3 (IPv4 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Create an EBGP peer group. |
group group-name external |
By default, no EBGP peer groups exist. |
4. Add a peer into the EBGP peer group. |
peer ipv4-address [ mask-length ] group group-name as-number as-number |
By default, no peers exist in the peer group. |
5. (Optional.) Configure a description for the peer group. |
peer group-name description text |
By default, no description is configured for the peer group. |
6. Create the BGP IPv4 unicast address family or BGP-VPN IPv4 unicast address family and enter its view. |
address-family ipv4 [ unicast ] |
By default, no BGP IPv4 unicast address family or BGP-VPN IPv4 unicast address family exists. |
7. Enable the router to exchange IPv4 unicast routing information with peers in the specified peer group. |
peer group-name enable |
By default, the router cannot exchange IPv4 unicast routing information with the peers. |
To configure an EBGP peer group by using Method 3 (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Create an EBGP peer group. |
group group-name external |
By default, no EBGP peer groups exist. |
4. Add a peer into the EBGP peer group. |
peer ipv6-address [ prefix-length ] group group-name as-number as-number |
By default, no peers exist in the peer group. |
5. (Optional.) Configure a description for the peer group. |
peer group-name description text |
By default, no description is configured for the peer group. |
6. Create the BGP IPv6 unicast address family or BGP-VPN IPv6 unicast address family and enter its view. |
address-family ipv6 [ unicast ] |
By default, no BGP IPv6 unicast address family or BGP-VPN IPv6 unicast address family exists. |
7. Enable the router to exchange IPv6 unicast routing information with peers in the specified peer group. |
peer group-name enable |
By default, the router cannot exchange IPv6 unicast routing information with the peers. |
To configure an EBGP peer group by using Method 3 (IPv4 multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view. |
bgp as-number [ instance instance-name ] [ multi-session-thread ] |
N/A |
3. Create an EBGP peer group. |
group group-name external |
By default, no EBGP peer groups exist. |
4. Add an IPv4 BGP peer into the EBGP peer group. |
peer ipv4-address [ mask-length ] group group-name as-number as-number |
By default, no peers exist in the peer group. |
5. (Optional.) Configure a description for the peer group. |
peer group-name description text |
By default, no description is configured for the peer group. |
6. Create the BGP IPv4 multicast address family and enter its view. |
address-family ipv4 multicast |
By default, no BGP IPv4 multicast address family exists. |
7. Enable the router to exchange IPv4 unicast routing information used for RPF check with peers in the specified peer group. |
peer group-name enable |
By default, the router cannot exchange IPv4 unicast routing information used for RPF check with the peers. |
Specifying the source address of TCP connections
By default, BGP uses the primary IPv4/IPv6 address of the output interface in the optimal route to a peer or peer group as the source address of TCP connections to the peer or peer group. You can change the source address in the following scenarios:
· If the peer's IPv4/IPv6 address belongs to an interface indirectly connected to the local router, specify that interface as the source interface for TCP connections on the peer. For example, interface A on the local end is directly connected to interface B on the peer. If you use the peer x.x.x.x as-number as-number command on the local end, and x.x.x.x is not the IPv4 address of interface B, you must do the following:
a. Use the peer connect-interface command on the peer.
b. Specify the interface whose IPv4 address is x.x.x.x as the source interface.
· If the source interface fails on a BGP router that has multiple links to a peer, BGP must re-establish TCP connections. To avoid this problem, use a loopback interface as the source interface or use the IP address of a loopback interface as the source address.
· If the BGP sessions use the IP addresses of different interfaces, specify a source address or source interface for each peer to establish multiple BGP sessions to a router. Specify a source address for each peer if the BGP sessions use the different addresses of the same interface. Otherwise, the local BGP router might fail to establish a TCP connection to a peer when it uses the optimal route to determine the source address.
To specify the source address of TCP connections (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Specify the source address of TCP connections to a peer or peer group. |
peer { group-name | ipv4-address [ mask-length ] } source-address source-ipv4-address |
By default, BGP uses the primary IPv4 address of the output interface in the optimal route to a peer or peer group as the source address of TCP connections to the peer or peer group. |
4. Specify the source interface of TCP connections to a peer or peer group. |
peer { group-name | ipv4-address [ mask-length ] } connect-interface interface-type interface-number |
To specify the source address of TCP connections (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Specify the source IPv6 address of TCP connections to a peer or peer group. |
peer { group-name | ipv6-address [ prefix-length ] } source-address source-ipv6-address |
By default, BGP uses the IPv6 address of the output interface in the optimal route to the BGP peer or peer group as the source address of TCP connections to the peer or peer group. |
4. Specify the source interface of TCP connections to a peer or peer group. |
peer { group-name | ipv6-address [ prefix-length ] } connect-interface interface-type interface-number |
Generating BGP routes
BGP can generate routes in the following ways:
· Advertise local networks.
· Redistribute IGP routes.
Injecting a local network
Perform this task to inject a network in the local routing table to the BGP routing table, so BGP can advertise the network to BGP peers. The ORIGIN attribute of BGP routes advertised in this way is IGP. You can also use a routing policy to control route advertisement.
The specified network must be available and active in the local IP routing table.
To inject a local network (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv4 unicast address family view, BGP-VPN IPv4 unicast address family view, or BGP IPv4 multicast address family view. |
· Enter BGP IPv4 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv4 [ unicast ] · Enter BGP-VPN IPv4 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv4 [ unicast ] · Enter BGP IPv4 multicast address family view: f. bgp as-number [ instance instance-name ] [ multi-session-thread ] g. address-family ipv4 multicast |
N/A |
3. Configure BGP to advertise a local network. |
network ipv4-address [ mask-length | mask ] [ route-policy route-policy-name ] |
By default, BGP does not advertise local networks. |
To inject a local network (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv6 unicast address family view or BGP-VPN IPv6 unicast address family view. |
· Enter BGP IPv6 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv6 [ unicast ] · Enter BGP-VPN IPv6 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv6 [ unicast ] |
N/A |
3. Configure BGP to advertise a local network. |
network ipv6-address prefix-length [ route-policy route-policy-name ] |
By default, BGP does not advertise local networks. |
Redistributing IGP routes
Perform this task to configure route redistribution from an IGP to BGP.
By default, BGP does not redistribute default IGP routes. You can use the default-route imported command to redistribute default IGP routes into the BGP routing table.
Only active routes can be redistributed. To view route state information, use the display ip routing-table protocol or display ipv6 routing-table protocol command.
The ORIGIN attribute of BGP routes redistributed from IGPs is INCOMPLETE.
To configure BGP to redistribute IGP routes (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv4 unicast address family view, BGP-VPN IPv4 unicast address family view, or BGP IPv4 multicast address family view. |
· Enter BGP IPv4 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv4 [ unicast ] · Enter BGP-VPN IPv4 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv4 [ unicast ] · Enter BGP IPv4 multicast address family view: f. bgp as-number [ instance instance-name ] [ multi-session-thread ] g. address-family ipv4 multicast |
N/A |
3. Enable route redistribution from the specified IGP into BGP. |
import-route protocol [ { process-id | all-processes } [ allow-direct | med med-value | route-policy route-policy-name ] * ] |
By default, BGP does not redistribute IGP routes. |
4. (Optional.) Enable default route redistribution into BGP. |
default-route imported |
By default, BGP does not redistribute default routes. |
To configure BGP to redistribute IGP routes (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv6 unicast address family view or BGP-VPN IPv6 unicast address family view. |
· Enter BGP IPv6 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv6 [ unicast ] · Enter BGP-VPN IPv6 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv6 [ unicast ] |
N/A |
3. Enable route redistribution from the specified IGP into BGP. |
import-route protocol [ { process-id | all-processes } [ allow-direct | med med-value | route-policy route-policy-name ] * ] |
By default, BGP does not redistribute IGP routes. |
4. (Optional.) Enable default route redistribution into BGP. |
default-route imported |
By default, BGP does not redistribute default routes. |
Controlling route distribution and reception
This section describes how to control route distribution and reception.
Configuring BGP route summarization
Route summarization can reduce the number of redistributed routes and the routing table size. IPv4 BGP supports automatic route summarization and manual route summarization. Manual summarization takes precedence over automatic summarization. IPv6 BGP supports only manual route summarization.
The output interface of a BGP summary route is Null 0 on the originating router. Therefore, a summary route must not be an optimal route on the originating router. Otherwise, BGP will fail to forward packets matching the route. If a summarized specific route has the same mask as the summary route, but has a lower priority, the summary route becomes the optimal route. To ensure correct packet forwarding, change the priority of the summary or specific route to make the specific route the optimal route.
Configuring automatic route summarization
Automatic route summarization enables BGP to summarize IGP subnet routes redistributed by the import-route command so BGP advertises only natural network routes.
To configure automatic route summarization (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv4 unicast address family view, BGP-VPN IPv4 unicast address family view, or BGP IPv4 multicast address family view. |
· Enter BGP IPv4 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv4 [ unicast ] · Enter BGP-VPN IPv4 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv4 [ unicast ] · Enter BGP IPv4 multicast address family view: f. bgp as-number [ instance instance-name ] [ multi-session-thread ] g. address-family ipv4 multicast |
N/A |
3. Configure automatic route summarization. |
summary automatic |
By default, automatic route summarization is not configured. |
Configuring manual route summarization
By configuring manual route summarization, you can do the following:
· Summarize both redistributed routes and routes injected using the network command.
· Determine the mask length for a summary route.
To configure BGP manual route summarization (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv4 unicast address family view, BGP-VPN IPv4 unicast address family view, or BGP IPv4 multicast address family view. |
· Enter BGP IPv4 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv4 [ unicast ] · Enter BGP-VPN IPv4 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv4 [ unicast ] · Enter BGP IPv4 multicast address family view: f. bgp as-number [ instance instance-name ] [ multi-session-thread ] g. address-family ipv4 multicast |
N/A |
3. Create a summary route in the BGP routing table. |
aggregate ipv4-address { mask-length | mask } [ as-set | attribute-policy route-policy-name | detail-suppressed | origin-policy route-policy-name | suppress-policy route-policy-name ] * |
By default, no summary routes are configured. |
To configure BGP manual route summarization (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv6 unicast address family view or BGP-VPN IPv6 unicast address family view. |
· Enter BGP IPv6 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv6 [ unicast ] · Enter BGP-VPN IPv6 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv6 [ unicast ] |
N/A |
3. Create a summary route in the IPv6 BGP routing table. |
aggregate ipv6-address prefix-length [ as-set | attribute-policy route-policy-name | detail-suppressed | origin-policy route-policy-name | suppress-policy route-policy-name ] * |
By default, no summary routes are configured. |
Advertising optimal routes in the IP routing table
By default, BGP advertises optimal routes in the BGP routing table, which may not be optimal in the IP routing table. This task allows you to advertise BGP routes that are optimal in the IP routing table.
To enable BGP to advertise optimal routes in the IP routing table (IPv4 unicast):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view. |
bgp as-number [ instance instance-name ] [ multi-session-thread ] |
N/A |
3. Enable BGP to advertise optimal routes in the IP routing table. |
advertise-rib-active |
By default, BGP advertises optimal routes in the BGP routing table. |
4. Enter BGP IPv4 unicast address family view or BGP-VPN IPv4 unicast address family view. |
·
Enter BGP IPv4 unicast address family view: · Enter BGP-VPN IPv4 unicast address family view: a. ip vpn-instance vpn-instance-name b. address-family ipv4 [ unicast ] |
N/A |
5. Enable BGP to advertise optimal routes in the IP routing table of the address family in the VPN instance. |
advertise-rib-active |
By default, the setting is the same as that in BGP instance view. |
To enable BGP to advertise optimal routes in the IPv6 routing table (IPv6 unicast):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view. |
bgp as-number [ instance instance-name ] [ multi-session-thread ] |
N/A |
3. Enable BGP to advertise optimal routes in the IPv6 routing table. |
advertise-rib-active |
By default, BGP advertises optimal routes in the BGP routing table. |
4. Enter BGP IPv6 unicast address family view or BGP-VPN IPv6 unicast address family view. |
·
Enter BGP IPv6 unicast address family view: · Enter BGP-VPN IPv6 unicast address family view: a. ip vpn-instance vpn-instance-name b. address-family ipv6 [ unicast ] |
N/A |
5. Enable BGP to advertise optimal routes in the IPv6 routing table of the address family in the VPN instance. |
advertise-rib-active |
By default, the setting is the same as that in BGP instance view. |
Advertising a default route to a peer or peer group
Perform this task to advertise a default BGP route with the next hop being the advertising router to a peer or peer group.
To advertise a default route to a peer or peer group (IPv4 unicast/multicast address family):
Command |
Remarks |
|
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv4 unicast address family view, BGP-VPN IPv4 unicast address family view, or BGP IPv4 multicast address family view. |
· Enter BGP IPv4 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv4 [ unicast ] · Enter BGP-VPN IPv4 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv4 [ unicast ] · Enter BGP IPv4 multicast address family view: f. bgp as-number [ instance instance-name ] [ multi-session-thread ] g. address-family ipv4 multicast |
N/A |
3. Advertise a default route to a peer or peer group. |
peer { group-name | ipv4-address [ mask-length ] } default-route-advertise [ route-policy route-policy-name ] |
By default, no default route is advertised. |
To advertise a default route to a peer or peer group (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv6 unicast address family view or BGP-VPN IPv6 unicast address family view. |
· Enter BGP IPv6 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv6 [ unicast ] · Enter BGP-VPN IPv6 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv6 [ unicast ] |
N/A |
3. Advertise a default route to a peer or peer group. |
peer { group-name | ipv6-address [ prefix-length ] } default-route-advertise [ route-policy route-policy-name ] |
By default, no default route is advertised. |
Limiting routes received from a peer or peer group
This feature can prevent attacks that send a large number of BGP routes to the router.
If the number of routes received from a peer or peer group exceeds the upper limit, the router takes one of the following actions based on your configuration:
· Tears down the BGP session to the peer or peer group and does not attempt to re-establish the session.
· Continues to receive routes from the peer or peer group and generates a log message.
· Retains the session to the peer or peer group, but it discards excess routes and generates a log message.
· Tears down the BGP session to the peer or peer group and, after a specific period of time, re-establishes a BGP session to the peer or peer group.
You can specify a percentage threshold for the router to generate a log message. When the ratio of the number of received routes to the maximum number reaches the percentage value, the router generates a log message.
To limit routes that a router can receive from a peer or peer group (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv4 unicast address family view, BGP-VPN IPv4 unicast address family view, or BGP IPv4 multicast address family view. |
· Enter BGP IPv4 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv4 [ unicast ] · Enter BGP-VPN IPv4 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv4 [ unicast ] · Enter BGP IPv4 multicast address family view: f. bgp as-number [ instance instance-name ] [ multi-session-thread ] g. address-family ipv4 multicast |
N/A |
3. Specify the maximum number of routes that a router can receive from a peer or peer group. |
peer { group-name | ipv4-address [ mask-length ] } route-limit prefix-number [ { alert-only | discard | reconnect reconnect-time } | percentage-value ] * |
By default, the number of routes that a router can receive from a peer or peer group is not limited. |
To limit routes that a router can receive from a peer or peer group (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv6 unicast address family view or BGP-VPN IPv6 unicast address family view. |
· Enter BGP IPv6 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv6 [ unicast ] · Enter BGP-VPN IPv6 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv6 [ unicast ] |
N/A |
3. Specify the maximum number of routes that a router can receive from a peer or peer group. |
peer { group-name | ipv6-address [ prefix-length ] } route-limit prefix-number [ { alert-only | discard | reconnect reconnect-time } | percentage-value ] * |
By default, the number of routes that a router can receive from a peer or peer group is not limited. |
Configuring BGP route filtering policies
Configuration prerequisites
Before you configure BGP routing filtering policies, configure the following filters used for route filtering as needed:
· ACL (see ACL and QoS Configuration Guide).
· Prefix list (see "Configuring routing policies").
· Routing policy (see "Configuring routing policies").
· AS path list (see "Configuring routing policies").
Configuring BGP route distribution filtering policies
To configure BGP route distribution filtering policies, use the following methods:
· Use an ACL or prefix list to filter routing information advertised to all peers.
· Use a routing policy, ACL, AS path list, or prefix list to filter routing information advertised to a peer or peer group.
If you configure multiple filtering policies, apply them in the following sequence:
1. filter-policy export
2. peer filter-policy export
3. peer as-path-acl export
4. peer prefix-list export
5. peer route-policy export
Only routes passing all the configured policies can be advertised.
To configure BGP route distribution filtering policies (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv4 unicast address family view, BGP-VPN IPv4 unicast address family view, or BGP IPv4 multicast address family view. |
· Enter BGP IPv4 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv4 [ unicast ] · Enter BGP-VPN IPv4 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv4 [ unicast ] · Enter BGP IPv4 multicast address family view: f. bgp as-number [ instance instance-name ] [ multi-session-thread ] g. address-family ipv4 multicast |
N/A |
3. Configure BGP route distribution filtering policies. |
·
Reference an ACL or IP prefix list to filter
advertised BGP routes: ·
Reference a routing policy to filter BGP
routes advertised to a peer or peer group: ·
Reference an ACL to filter BGP routes
advertised to a peer or peer group: ·
Reference an AS path list to filter BGP
routes advertised to a peer or peer group: ·
Reference an IPv4 prefix list to filter BGP
routes advertised to a peer or peer group: |
Use at least one method. By default, no BGP distribution filtering policy is configured. |
To configure BGP route distribution filtering policies (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv6 unicast address family view or BGP-VPN IPv6 unicast address family view. |
· Enter BGP IPv6 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv6 [ unicast ] · Enter BGP-VPN IPv6 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv6 [ unicast ] |
N/A |
3. Configure BGP route distribution filtering policies. |
·
Reference an ACL or IPv6 prefix list to filter
advertised BGP routes: ·
Reference a routing policy to filter BGP
routes advertised to a peer or peer group: ·
Reference an ACL to filter BGP routes
advertised to a peer or peer group: ·
Reference an AS path list to filter BGP
routes advertised to a peer or peer group: ·
Reference an IPv6 prefix list to filter BGP
routes advertised to a peer or peer group |
Use at least one method. By default, no BGP distribution filtering policy is configured. |
Configuring BGP route reception filtering policies
You can use the following methods to configure BGP route reception filtering policies:
· Use an ACL or prefix list to filter routing information received from all peers.
· Use a routing policy, ACL, AS path list, or prefix list to filter routing information received from a peer or peer group.
If you configure multiple filtering policies, apply them in the following sequence:
1. filter-policy import
2. peer filter-policy import
3. peer as-path-acl import
4. peer prefix-list import
5. peer route-policy import
Only routes passing all the configured policies can be received.
To configure BGP route reception filtering policies (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv4 unicast address family view, BGP-VPN IPv4 unicast address family view, or BGP IPv4 multicast address family view. |
· Enter BGP IPv4 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv4 [ unicast ] · Enter BGP-VPN IPv4 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv4 [ unicast ] · Enter BGP IPv4 multicast address family view: f. bgp as-number [ instance instance-name ] [ multi-session-thread ] g. address-family ipv4 multicast |
N/A |
3. Configure BGP route reception filtering policies. |
·
Reference an ACL or IP prefix list to filter
BGP routes received from all peers: ·
Reference a routing policy to filter BGP
routes received from a peer or peer group: ·
Reference an ACL to filter BGP routes received
from a peer or peer group: ·
Reference an AS path list to filter BGP
routes received from a peer or peer group: ·
Reference an IPv4 prefix list to filter BGP
routes received from a peer or peer group: |
Use at least one method. By default, no route reception filtering is configured. |
To configure BGP route reception filtering policies (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv6 unicast address family view or BGP-VPN IPv6 unicast address family view. |
· Enter BGP IPv6 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv6 [ unicast ] · Enter BGP-VPN IPv6 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv6 [ unicast ] |
N/A |
3. Configure BGP route reception filtering policies. |
·
Reference ACL or IPv6 prefix list to filter
BGP routes received from all peers: ·
Reference a routing policy to filter BGP
routes received from a peer or peer group: ·
Reference an ACL to filter BGP routes received
from a peer or peer group: ·
Reference an AS path list to filter BGP routes
received from a peer or peer group: ·
Reference an IPv6 prefix list to filter BGP
routes received from a peer or peer group: |
Use at least one method. By default, no route reception filtering is configured. |
Configuring BGP route update delay
Perform this task to configure BGP to delay sending route updates on reboot to reduce traffic loss. With this feature enabled, BGP redistributes all routes from other neighbors on reboot, selects the optimal route, and then advertises it.
To configure BGP route update delay:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view. |
bgp as-number [ instance instance-name ] [ multi-session-thread ] |
N/A |
3. Configure BGP to delay sending route updates on reboot. |
bgp update-delay on-startup seconds |
By default, BGP immediately sends route updates on reboot. |
4. (Optional.) Configure BGP to immediately send route updates for routes that match a prefix list. |
bgp update-delay on-startup prefix-list prefix-list-name |
By default, no prefix list is specified to filter routes. Use this command when the updates for the specified routes must be sent immediately. This command is available only to IPv4 prefix lists. |
Configuring BGP route dampening
Route dampening enables BGP to not select unstable routes as optimal routes. This feature applies to EBGP routes but not to IBGP routes.
If an EBGP peer goes down after you configure this feature, routes coming from the peer are dampened but not deleted.
To configure BGP route dampening (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv4 unicast address family view, BGP-VPN IPv4 unicast address family view, or BGP IPv4 multicast address family view. |
· Enter BGP IPv4 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv4 [ unicast ] · Enter BGP-VPN IPv4 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv4 [ unicast ] · Enter BGP IPv4 multicast address family view: f. bgp as-number [ instance instance-name ] [ multi-session-thread ] g. address-family ipv4 multicast |
N/A |
3. Configure BGP route dampening. |
dampening [ half-life-reachable half-life-unreachable reuse suppress ceiling | route-policy route-policy-name ] * |
By default, BGP route dampening is not configured. |
To configure BGP route dampening (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv6 unicast address family view or BGP-VPN IPv6 unicast address family view. |
· Enter BGP IPv6 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv6 [ unicast ] · Enter BGP-VPN IPv6 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv6 [ unicast ] |
N/A |
3. Configure IPv6 BGP route dampening. |
dampening [ half-life-reachable half-life-unreachable reuse suppress ceiling | route-policy route-policy-name ] * |
By default, IPv6 BGP route dampening is not configured. |
Controlling BGP path selection
By configuring BGP path attributes, you can control BGP path selection.
Setting a preferred value for routes received
Perform this task to set a preferred value for specific routes to control BGP path selection.
Among multiple routes that have the same destination/mask and are learned from different peers, the one with the greatest preferred value is selected as the optimal route.
To set a preferred value for routes from a peer or peer group (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv4 unicast address family view, BGP-VPN IPv4 unicast address family view, or BGP IPv4 multicast address family view. |
· Enter BGP IPv4 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv4 [ unicast ] · Enter BGP-VPN IPv4 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv4 [ unicast ] · Enter BGP IPv4 multicast address family view: f. bgp as-number [ instance instance-name ] [ multi-session-thread ] g. address-family ipv4 multicast |
N/A |
3. Set a preferred value for routes received from a peer or peer group. |
peer { group-name | ipv4-address [ mask-length ] } preferred-value value |
The default preferred value is 0. |
To set a preferred value for routes from a peer or peer group (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv6 unicast address family view or BGP-VPN IPv6 unicast address family view. |
· Enter BGP IPv6 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv6 [ unicast ] · Enter BGP-VPN IPv6 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv6 [ unicast ] |
N/A |
3. Set a preferred value for routes received from a peer or peer group. |
peer { group-name | ipv6-address [ prefix-length ] } preferred-value value |
The default preferred value is 0. |
Configuring preferences for BGP routes
Routing protocols each have a default preference. If they find multiple routes destined for the same network, the route found by the routing protocol with the highest preference is selected as the optimal route.
You can use the preference command to modify preferences for EBGP, IBGP, and local BGP routes, or use a routing policy to set a preference for matching routes. For routes not matching the routing policy, the default preference applies.
If a device has an EBGP route and a local BGP route to reach the same destination, it does not select the EBGP route because the EBGP route has a lower preference than the local BGP route by default. You can use the network short-cut command to configure the EBGP route as a shortcut route that has the same preference as the local BGP route. The EBGP route will more likely become the optimal route.
To configure preferences for BGP routes (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv4 unicast address family view, BGP-VPN IPv4 unicast address family view, or BGP IPv4 multicast address family view. |
· Enter BGP IPv4 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv4 [ unicast ] · Enter BGP-VPN IPv4 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv4 [ unicast ] · Enter BGP IPv4 multicast address family view: f. bgp as-number [ instance instance-name ] [ multi-session-thread ] g. address-family ipv4 multicast |
N/A |
3. Configure preferences for EBGP, IBGP, and local BGP routes. |
preference { external-preference internal-preference local-preference | route-policy route-policy-name } |
The default preferences for EBGP, IBGP, and local BGP routes are 255, 255, and 130. |
4. Configure an EBGP route as a shortcut route. |
network ipv4-address [ mask-length | mask ] short-cut |
By default, an EBGP route has a preference of 255. |
To configure preferences for BGP routes (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv6 unicast address family view or BGP-VPN IPv6 unicast address family view. |
· Enter BGP IPv6 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv6 [ unicast ] · Enter BGP-VPN IPv6 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv6 [ unicast ] |
N/A |
3. Configure preferences for EBGP, IBGP, and local BGP routes. |
preference { external-preference internal-preference local-preference | route-policy route-policy-name } |
The default preferences for EBGP, IBGP, and local BGP routes are 255, 255, and 130. |
4. Configure an EBGP route as a shortcut route. |
network ipv6-address prefix-length short-cut |
By default, an EBGP route has a preference of 255. |
Configuring the default local preference
The local preference is used to determine the optimal route for traffic leaving the local AS. When a BGP router obtains from several IBGP peers multiple routes to the same destination, but with different next hops, it considers the route with the highest local preference as the optimal route.
This task allows you to specify the default local preference for routes sent to IBGP peers.
To specify the default local preference (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv4 unicast address family view, BGP-VPN IPv4 unicast address family view, or BGP IPv4 multicast address family view. |
· Enter BGP IPv4 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv4 [ unicast ] · Enter BGP-VPN IPv4 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv4 [ unicast ] · Enter BGP IPv4 multicast address family view: f. bgp as-number [ instance instance-name ] [ multi-session-thread ] g. address-family ipv4 multicast |
N/A |
3. Configure the default local preference. |
default local-preference value |
The default local preference is 100. |
To specify the default local preference (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv6 unicast address family view or BGP-VPN IPv6 unicast address family view. |
· Enter BGP IPv6 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv6 [ unicast ] · Enter BGP-VPN IPv6 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv6 [ unicast ] |
N/A |
3. Configure the default local preference. |
default local-preference value |
The default local preference is 100. |
Configuring the MED attribute
BGP uses MED to determine the optimal route for traffic going into an AS. When a BGP router obtains multiple routes with the same destination but with different next hops, it considers the route with the smallest MED value as the optimal route if other conditions are the same.
Configuring the default MED value
To configure the default MED value (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv4 unicast address family view, BGP-VPN IPv4 unicast address family view, or BGP IPv4 multicast address family view. |
· Enter BGP IPv4 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv4 [ unicast ] · Enter BGP-VPN IPv4 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv4 [ unicast ] · Enter BGP IPv4 multicast address family view: f. bgp as-number [ instance instance-name ] [ multi-session-thread ] g. address-family ipv4 multicast |
N/A |
3. Configure the default MED value. |
default med med-value |
The default MED value is 0. |
To configure the default MED value (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv6 unicast address family view or BGP-VPN IPv6 unicast address family view. |
· Enter BGP IPv6 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv6 [ unicast ] · Enter BGP-VPN IPv6 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv6 [ unicast ] |
N/A |
3. Configure the default MED value. |
default med med-value |
The default MED value is 0. |
Enabling MED comparison for routes from different ASs
This task enables BGP to compare the MEDs of routes from different ASs.
To enable MED comparison for routes from different ASs:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Enable MED comparison for routes from different ASs. |
compare-different-as-med |
By default, MED comparison for routes from different ASs is disabled. |
Enabling MED comparison for routes on a per-AS basis
This task enables BGP to compare the MEDs of routes from an AS.
Figure 59 Route selection based on MED (in an IPv4 network)
As shown in Figure 59, Router D establishes indirect EBGP peer relationships with Router A, Router B, and Router C, and learns addresses 1.1.1.1/32, 2.2.2.2/32, and 3.3.3.3/32 through OSPF. The following output shows the routing information on Router D.
Destination/Mask Proto Pre Cost NextHop Interface
1.1.1.1/32 O_INTRA 10 10 11.1.1.2 HGE1/0/1
2.2.2.2/32 O_INTRA 10 20 12.1.1.2 HGE1/0/2
3.3.3.3/32 O_INTRA 10 30 13.1.1.2 HGE1/0/3
Router D learns network 10.0.0.0 from both Router A and Router B. Because the route learned from Router B has a smaller IGP metric, the route is optimal. The following output shows the BGP routing table on Router D.
Network NextHop MED LocPrf PrefVal Path/Ogn
*>e 10.0.0.0 2.2.2.2 50 0 300 400e
* e 3.3.3.3 50 0 200 400e
When Router D learns network 10.0.0.0 from Router C, it compares the route with the optimal route in its routing table. Because Router C and Router B reside in different ASs, BGP does not compare the MEDs of the two routes. The route from Router C has a smaller IGP metric than the route from Router B, so the route from Router C becomes optimal. The following output shows the BGP routing table on Router D.
Network NextHop MED LocPrf PrefVal Path/Ogn
*>e 10.0.0.0 1.1.1.1 60 0 200 400e
* e 10.0.0.0 2.2.2.2 50 0 300 400e
* e 3.3.3.3 50 0 200 400e
However, Router C and Router A reside in the same AS, and Router C has a greater MED, so network 10.0.0.0 learned from Router C should not be optimal.
To avoid this problem, you can configure the bestroute compare-med command to enable MED comparison for routes from the same AS on Router D. After that, Router D puts the routes received from each AS into a group, selects the route with the lowest MED from each group, and compares routes from different groups. Network 10.0.0.0 learned from Router B is the optimal route. The following output shows the BGP routing table on Router D.
Network NextHop MED LocPrf PrefVal Path/Ogn
*>e 10.0.0.0 2.2.2.2 50 0 300 400e
* e 3.3.3.3 50 0 200 400e
* e 1.1.1.1 60 0 200 400e
To enable MED comparison for routes on a per-AS basis:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Enable MED comparison for routes on a per-AS basis. |
bestroute compare-med |
By default, MED comparison for routes on a per-AS basis is disabled. |
Enabling MED comparison for routes from confederation peers
This task enables BGP to compare the MEDs of routes received from confederation peers. However, if a route received from a confederation peer has an AS number that does not belong to the confederation, BGP does not compare the route with other routes. For example, a confederation has three AS numbers 65006, 65007, and 65009. BGP receives three routes from different confederation peers. The AS_PATH attributes of these routes are 65006 65009, 65007 65009, and 65008 65009, and the MED values of them are 2, 3, and 1. Because the third route's AS_PATH attribute contains AS number 65008 that does not belong to the confederation, BGP does not compare it with other routes. As a result, the first route becomes the optimal route.
To enable MED comparison for routes from confederation peers:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Enable MED comparison for routes from confederation peers. |
bestroute med-confederation |
By default, MED comparison for routes from confederation peers is disabled. |
Configuring the NEXT_HOP attribute
By default, a BGP router does not set itself as the next hop for routes advertised to an IBGP peer or peer group. In some cases, however, you must configure the advertising router as the next hop to ensure that the BGP peer can find the correct next hop.
For example, as shown in Figure 60, Router A and Router B establish an EBGP neighbor relationship, and Router B and Router C establish an IBGP neighbor relationship. If Router C has no route destined for IP address 1.1.1.1/24, you must configure Router B to set itself 3.1.1.1/24 as the next hop for the network 2.1.1.1/24 advertised to Router C.
Figure 60 NEXT_HOP attribute configuration
If a BGP router has two peers on a broadcast network, it does not set itself as the next hop for routes sent to an EBGP peer by default. As shown in Figure 61, Router A and Router B establish an EBGP neighbor relationship, and Router B and Router C establish an IBGP neighbor relationship. They are on the same broadcast network 1.1.1.0/24. When Router B sends EBGP routes to Router A, it does not set itself as the next hop by default. However, you can configure Router B to set it (1.1.1.2/24) as the next hop for routes sent to Router A by using the peer next-hop-local command as needed.
Figure 61 NEXT_HOP attribute configuration
|
IMPORTANT: If you have configured BGP load balancing, the router sets itself as the next hop for routes sent to an IBGP peer or peer group regardless of whether the peer next-hop-local command is configured. |
To configure the NEXT_HOP attribute (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv4 unicast address family view, BGP-VPN IPv4 unicast address family view, or BGP IPv4 multicast address family view. |
· Enter BGP IPv4 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv4 [ unicast ] · Enter BGP-VPN IPv4 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv4 [ unicast ] · Enter BGP IPv4 multicast address family view: f. bgp as-number [ instance instance-name ] [ multi-session-thread ] g. address-family ipv4 multicast |
N/A |
3. Specify the router as the next hop for routes sent to a peer or peer group. |
peer { group-name | ipv4-address [ mask-length ] } next-hop-local |
By default, the router sets itself as the next hop for routes sent to an EBGP peer or peer group. However, it does not set itself as the next hop for routes sent to an IBGP peer or peer group. |
To configure the NEXT_HOP attribute (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv6 unicast address family view or BGP-VPN IPv6 unicast address family view. |
· Enter BGP IPv6 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv6 [ unicast ] · Enter BGP-VPN IPv6 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv6 [ unicast ] |
N/A |
3. Specify the router as the next hop for routes sent to a peer or peer group. |
peer { group-name | ipv6-address [ prefix-length ] } next-hop-local |
By default, the router sets itself as the next hop for routes sent to an EBGP peer or peer group. However, it does not set itself as the next hop for routes sent to an IBGP peer or peer group. |
Configuring the AS_PATH attribute
Permitting local AS number to appear in routes from a peer or peer group
In general, BGP checks whether the AS_PATH attribute of a route from a peer contains the local AS number. If yes, it discards the route to avoid routing loops.
In certain network environments (for example, a Hub&Spoke network in MPLS L3VPN), however, the AS_PATH attribute of a route from a peer must be allowed to contain the local AS number. Otherwise, the route cannot be advertised correctly.
To permit the local AS number to appear in routes from a peer or peer group and specify the appearance times (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv4 unicast address family view, BGP-VPN IPv4 unicast address family view, or BGP IPv4 multicast address family view. |
· Enter BGP IPv4 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv4 [ unicast ] · Enter BGP-VPN IPv4 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv4 [ unicast ] · Enter BGP IPv4 multicast address family view: f. bgp as-number [ instance instance-name ] [ multi-session-thread ] g. address-family ipv4 multicast |
N/A |
3. Permit the local AS number to appear in routes from a peer or peer group and set the appearance times. |
peer { group-name | ipv4-address [ mask-length ] } allow-as-loop [ number ] |
By default, the local AS number is not allowed in routes from a peer or peer group. |
To permit the local AS number to appear in routes from a peer or peer group and specify the appearance times (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv6 unicast address family view or BGP-VPN IPv6 unicast address family view. |
· Enter BGP IPv6 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv6 [ unicast ] · Enter BGP-VPN IPv6 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv6 [ unicast ] |
N/A |
3. Permit the local AS number to appear in routes from a peer or peer group and set the appearance times. |
peer { group-name | ipv6-address [ prefix-length ] } allow-as-loop [ number ] |
By default, the local AS number is not allowed in routes from a peer or peer group. |
Ignoring the AS_PATH attribute during optimal route selection
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Configure BGP to ignore the AS_PATH attribute during optimal route selection |
bestroute as-path-neglect |
By default, BGP considers AS_PATH during optimal route selection. |
Advertising a fake AS number to a peer or peer group
After you move a BGP router from an AS to another AS (from AS 2 to AS 3 for example), you have to modify the AS number of the router on all its EBGP peers. To avoid such modifications, you can configure the router to advertise a fake AS number 2 to its EBGP peers so that the EBGP peers still think that Router A is in AS 2.
To advertise a fake AS number to a peer or peer group (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Advertise a fake AS number to a peer or peer group. |
peer { group-name | ipv4-address [ mask-length ] } fake-as as-number |
By default, no fake AS number is advertised to a peer or peer group. This command applies only to EBGP peers or EBGP peer groups. |
To advertise a fake AS number to a peer or peer group (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Advertise a fake AS number to a peer or peer group. |
peer { group-name | ipv6-address [ prefix-length ] } fake-as as-number |
By default, no fake AS number is advertised to a peer or peer group. This command applies only to EBGP peers or EBGP peer groups. |
Configuring AS number substitution
|
IMPORTANT: Do not configure AS number substitution in normal circumstances. Otherwise, routing loops might occur. |
To use EBGP between PE and CE in MPLS L3VPN, VPN sites in different geographical areas should have different AS numbers. Otherwise, BGP discards route updates containing the local AS number. If two CEs connected to different PEs use the same AS number, you must configure AS number substitution on each PE. This substitution can replace the AS number in route updates originated by the remote CE as its own AS number before advertising them to the connected CE.
Figure 62 AS number substitution configuration (in an IPv4 network)
As shown in Figure 62, CE 1 and CE 2 use the same AS number 800. To ensure bidirectional communication between the two sites, configure AS number substitution on PE 2. PE 2 replaces AS 800 with AS 100 for the BGP route update originated from CE 1 before advertising it to CE 2. Perform the same configuration on PE 1.
To configure AS number substitution for a peer or peer group (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Configure AS number substitution for a peer or peer group. |
peer { group-name | ipv4-address [ mask-length ] } substitute-as |
By default, AS number substitution is not configured. |
To configure AS number substitution for a peer or peer group (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Configure AS number substitution for a peer or peer group. |
peer { group-name | ipv6-address [ prefix-length ] } substitute-as |
By default, AS number substitution is not configured. |
Removing private AS numbers from updates sent to an EBGP peer or peer group
Private AS numbers are typically used in test networks, and should not be transmitted in public networks. The range of private AS numbers is from 64512 to 65535.
To remove private AS numbers from updates sent to an EBGP peer or peer group (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv4 unicast address family view, BGP-VPN IPv4 unicast address family view, or BGP IPv4 multicast address family view. |
· Enter BGP IPv4 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv4 [ unicast ] · Enter BGP-VPN IPv4 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv4 [ unicast ] · Enter BGP IPv4 multicast address family view: f. bgp as-number [ instance instance-name ] [ multi-session-thread ] g. address-family ipv4 multicast |
N/A |
3. Configure BGP to remove private AS numbers from the AS_PATH attribute of updates sent to an EBGP peer or peer group. |
peer { group-name | ipv4-address [ mask-length ] } public-as-only |
By default, BGP updates sent to an EBGP peer or peer group can carry both public and private AS numbers. This command is applicable only to EBGP peers or peer groups. |
To remove private AS numbers from updates sent to an EBGP peer or peer group (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv6 unicast address family view or BGP-VPN IPv6 unicast address family view. |
· Enter BGP IPv6 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv6 [ unicast ] · Enter BGP-VPN IPv6 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv6 [ unicast ] |
N/A |
3. Configure BGP to remove private AS numbers from the AS_PATH attribute of updates sent to an EBGP peer or peer group. |
peer { group-name | ipv6-address [ prefix-length ] } public-as-only |
By default, BGP updates sent to an EBGP peer or peer group can carry both public and private AS numbers. This command is applicable only to EBGP peers or peer groups. |
Ignoring the first AS number of EBGP route updates
By default, BGP checks the first AS number of a received EBGP route update. If the first AS number is neither the AS number of the BGP peer nor a private AS number, the BGP router disconnects the BGP session to the peer.
To ignore the first AS number of EBGP route updates:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view. |
bgp as-number [ instance instance-name ] [ multi-session-thread ] |
N/A |
3. Configure BGP to ignore the first AS number of EBGP route updates. |
ignore-first-as |
By default, BGP checks the first AS number of EBGP route updates. |
Ignoring IGP metrics during optimal route selection
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Configure BGP to ignore IGP metrics during optimal route selection. |
bestroute igp-metric-ignore |
By default, BGP considers IGP metrics during optimal route selection. If multiple routes to the same destination are available, BGP selects the route with the smallest IGP metric as the optimal route. |
Configuring the SoO attribute
After you configure the SoO attribute for a BGP peer or peer group, BGP adds the SoO attribute into the route updates received from the BGP peer or peer group. In addition, before advertising route updates to the peer or peer group, BGP checks the SoO attribute of the route update against the configured SoO attribute. If they are the same, BGP does not advertise the route updates to the BGP peer or peer group.
To configure the SoO attribute (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv4 unicast address family view, BGP-VPN IPv4 unicast address family view, or BGP IPv4 multicast address family view. |
· Enter BGP IPv4 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv4 [ unicast ] · Enter BGP-VPN IPv4 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv4 [ unicast ] · Enter BGP IPv4 multicast address family view: f. bgp as-number [ instance instance-name ] [ multi-session-thread ] g. address-family ipv4 multicast |
N/A |
3. Configure the SoO attribute for a peer or peer group. |
peer { group-name | ipv4-address [ mask-length ] } soo site-of-origin |
By default, no SoO attribute is configured for a peer or peer group. |
To configure the SoO attribute (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv6 unicast address family view or BGP-VPN IPv6 unicast address family view. |
· Enter BGP IPv6 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv6 [ unicast ] · Enter BGP-VPN IPv6 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv6 [ unicast ] |
N/A |
3. Configure the SoO attribute for a peer or peer group. |
peer { group-name | ipv6-address [ prefix-length ] } soo site-of-origin |
By default, no SoO attribute is configured for a peer or peer group. |
Tuning and optimizing BGP networks
This section describes how to tune and optimize BGP networks.
Configuring the keepalive interval and hold time
BGP sends keepalive messages regularly to keep the BGP session between two routers.
If a router receives no keepalive or update message from a peer within the hold time, it tears down the session.
You can configure the keepalive interval and hold time globally or for a peer or peer group. The individual settings take precedence over the global settings.
The actual keepalive interval and hold time are determined as follows:
· If the hold time settings on the local and peer routers are different, the smaller setting is used. If the hold time is 0, BGP does not send keepalive messages to its peers and never tears down the session.
· If the keepalive interval is not 0, the actual keepalive interval is the smaller one between 1/3 of the hold time and the keepalive interval.
To configure the keepalive interval and hold time (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Configure the keepalive interval and hold time. |
·
Configure the global keepalive interval
and hold time: ·
Configure the keepalive interval and
hold time for a peer or peer group: |
Use at least one method. By default, the keepalive interval is 60 seconds, and hold time is 180 seconds. The timer command takes effect for new BGP sessions and does not affect existing sessions. The timers configured with the timer and peer timer commands do not take effect until a session is re-established (for example, a session is reset). The hold time must be at least three times the keepalive interval. |
To configure the keepalive interval and hold time (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Configure the keepalive interval and hold time. |
·
Configure the global keepalive interval
and hold time: ·
Configure the keepalive interval and
hold time for a peer or peer group: |
Use at least one method. By default, the keepalive interval is 60 seconds, and hold time is 180 seconds. The timer command takes effect for new BGP sessions and does not affect existing sessions. The timers configured with the timer and peer timer commands do not take effect until a session is re-established (for example, a session is reset). The hold time must be at least three times the keepalive interval. |
Configuring the interval for sending updates for the same route
A BGP router sends an update message to its peers when a route is changed. If the route changes frequently, the BGP router keeps sending updates for the same route, resulting route flapping. To prevent this situation, perform this task to configure the interval for sending updates for the same route to a peer or peer group.
To configure the interval for sending the same update to a peer or peer group (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Configure the interval for sending updates for the same route to a peer or peer group. |
peer { group-name | ipv4-address [ mask-length ] } route-update-interval interval |
By default, the interval is 15 seconds for an IBGP peer and 30 seconds for an EBGP peer. |
To configure the interval for sending the same update to a peer or peer group (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Configure the interval for sending updates for the same route to a peer or peer group. |
peer { group-name | ipv6-address [ prefix-length ] } route-update-interval interval |
By default, the interval is 15 seconds for an IBGP peer and 30 seconds for an EBGP peer. |
Enabling BGP to establish an EBGP session over multiple hops
To establish an EBGP session, two routers must have a direct physical link and use directly connected interfaces. If no direct link is available, you must use the peer ebgp-max-hop command to enable BGP to establish an EBGP session over multiple hops and specify the maximum hops.
When the BGP GTSM feature is enabled, two peers can establish an EBGP session after passing GTSM check, regardless of whether the maximum number of hops is reached.
To enable BGP to establish an indirect EBGP session (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Enable BGP to establish an EBGP session to an indirectly connected peer or peer group and specify the maximum hop count. |
peer { group-name | ipv4-address [ mask-length ] } ebgp-max-hop [ hop-count ] |
By default, BGP cannot establish an EBGP session to an indirectly connected peer or peer group. |
To enable BGP to establish an indirect EBGP session (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Enable BGP to establish an EBGP session to an indirectly connected peer or peer group and specify the maximum hop count. |
peer { group-name | ipv6-address [ prefix-length ] } ebgp-max-hop [ hop-count ] |
By default, BGP cannot establish an EBGP session to an indirectly connected peer or peer group. |
Enabling immediate re-establishment of direct EBGP connections upon link failure
When the link to a directly connected EBGP peer goes down, the router does not re-establish a session to the peer until the hold time timer expires. This feature enables BGP to immediately recreate the session in that situation. When this feature is disabled, route flapping does not affect EBGP session state.
To enable immediate re-establishment of direct EBGP connections:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view. |
bgp as-number [ instance instance-name ] [ multi-session-thread ] |
N/A |
3. Enable immediate re-establishment of direct EBGP connections upon link failure. |
ebgp-interface-sensitive |
By default, immediate re-establishment of direct EBGP connections is enabled. |
Enabling 4-byte AS number suppression
BGP supports 4-byte AS numbers. The 4-byte AS number occupies four bytes, in the range of 1 to 4294967295. By default, a device sends an Open message to the peer device for session establishment. The Open message indicates that the device supports 4-byte AS numbers. If the peer device supports 2-byte AS numbers instead of 4-byte AS numbers, the session cannot be established. To resolve this issue, enable the 4-byte AS number suppression feature. The device then sends an Open message to inform the peer that it does not support 4-byte AS numbers, so the BGP session can be established.
If the peer device supports 4-byte AS numbers, do not enable the 4-byte AS number suppression feature. Otherwise, the BGP session cannot be established.
To enable 4-byte AS number suppression (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Enable 4-byte AS number suppression. |
peer { group-name | ipv4-address [ mask-length ] } capability-advertise suppress-4-byte-as |
By default, 4-byte AS number suppression is disabled. |
To enable 4-byte AS number suppression (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Enable 4-byte AS number suppression. |
peer { group-name | ipv6-address [ prefix-length ] } capability-advertise suppress-4-byte-as |
By default, 4-byte AS number suppression is disabled. |
Enabling MD5 authentication for BGP peers
MD5 authentication provides the following benefits:
· Peer authentication ensures that only BGP peers that have the same password can establish TCP connections.
· Integrity check ensures that BGP packets exchanged between peers are intact.
To enable MD5 authentication for BGP peers (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Enable MD5 authentication for a BGP peer group or peer. |
peer { group-name | ipv4-address [ mask-length ] } password { cipher | simple } password |
By default, MD5 authentication is disabled. |
To enable MD5 authentication for BGP peers (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Enable MD5 authentication for a BGP peer group or peer. |
peer { group-name | ipv6-address [ prefix-length ] } password { cipher | simple } password |
By default, MD5 authentication is disabled. |
Enabling keychain authentication for BGP peers
Keychain authentication enhances the security of TCP connection establishment between BGP peers. It allows BGP peers to establish TCP connections only when the following conditions are met:
· Keychain authentication is enabled on both BGP peers.
· The keys used by the BGP peers have the same authentication algorithm and key string.
Before configuring keychain authentication, make sure the specified keychain has been created.
For more information about keychains, see Security Configuration Guide.
To enable keychain authentication for BGP peers (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view of BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Enable keychain authentication for a BGP peer or peer group. |
peer { group-name | ip-address [ mask-length ] } keychain keychain-name |
By default, keychain authentication is disabled. |
To enable keychain authentication for BGP peers (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Enable keychain authentication for a BGP peer or peer group. |
peer { group-name | ipv6-address [ prefix-length ] } keychain keychain-name |
By default, keychain authentication is disabled. |
Configuring BGP load balancing
Perform this task to specify the maximum number of BGP ECMP routes for load balancing.
To specify the maximum number of BGP ECMP routes for load balancing (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
|
1. Enter system view. |
system-view |
N/A |
|
2. Enter BGP IPv4 unicast address family view, BGP-VPN IPv4 unicast address family view, or BGP IPv4 multicast address family view. |
· Enter BGP IPv4 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv4 [ unicast ] · Enter BGP-VPN IPv4 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv4 [ unicast ] · Enter BGP IPv4 multicast address family view: f. bgp as-number [ instance instance-name ] [ multi-session-thread ] g. address-family ipv4 multicast |
N/A |
|
3. Specify the maximum number of BGP ECMP routes for load balancing. |
balance [ ebgp | eibgp | ibgp ] number |
By default, load balancing is disabled. |
|
4. (Optional.) Enable BGP to ignore the AS_PATH attribute when it implements load balancing. |
balance as-path-neglect |
By default, BGP does not ignore the AS_PATH attribute when it implements load balancing. |
|
To specify the maximum number of BGP ECMP routes for load balancing (IPv6 unicast address family):
Step |
Command |
Remarks |
|
1. Enter system view. |
system-view |
N/A |
|
2. Enter BGP IPv6 unicast address family view or BGP-VPN IPv6 unicast address family view. |
· Enter BGP IPv6 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv6 [ unicast ] · Enter BGP-VPN IPv6 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv6 [ unicast ] |
N/A |
|
3. Specify the maximum number of BGP ECMP routes for load balancing. |
balance [ ebgp | eibgp | ibgp ] number |
By default, load balancing is disabled. |
|
4. (Optional.) Enable BGP to ignore the AS_PATH attribute when it implements load balancing. |
balance as-path-neglect |
By default, BGP does not ignore the AS_PATH attribute when it implements load balancing. |
|
Disabling BGP to establish a session to a peer or peer group
This task enables you to temporarily tear down the BGP session to a peer or peer group. Then you can perform network upgrade and maintenance without needing to delete and reconfigure the peer or peer group. To recover the session, execute the undo peer ignore command.
To disable BGP to establish a session to a peer or peer group (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Disable BGP to establish a session to a peer or peer group. |
peer { group-name | ipv4-address [ mask-length ] } ignore |
By default, BGP can establish a session to a peer or peer group. |
To disable BGP to establish a session to a peer or peer group (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Disable BGP to establish a session to a peer or peer group. |
peer { group-name | ipv6-address [ prefix-length ] } ignore |
By default, BGP can establish a session to a peer. |
Configuring GTSM for BGP
The Generalized TTL Security Mechanism (GTSM) protects a BGP session by comparing the TTL value in the IP header of incoming BGP packets against a valid TTL range. If the TTL value is within the valid TTL range, the packet is accepted. If not, the packet is discarded.
The valid TTL range is from 255 – the configured hop count + 1 to 255.
When GTSM is configured, the BGP packets sent by the device have a TTL of 255.
GTSM provides best protection for directly connected EBGP sessions, but not for multihop EBGP or IBGP sessions because the TTL of packets might be modified by intermediate devices.
|
IMPORTANT: · When GTSM is configured, the local device can establish an EBGP session to the peer after both devices pass GTSM check, regardless of whether the maximum number of hops is reached. · To use GTSM, you must configure GTSM on both the local and peer devices. You can specify different hop-count values for them. |
To configure GTSM for BGP (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Configure GTSM for the specified BGP peer or peer group. |
peer { group-name | ipv4-address [ mask-length ] } ttl-security hops hop-count |
By default, GTSM is disabled. |
To configure GTSM for BGP (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Configure GTSM for the specified BGP peer or peer group. |
peer { group-name | ipv6-address [ prefix-length ] } ttl-security hops hop-count |
By default, GTSM is disabled. |
Configuring BGP soft-reset
After you modify the route selection policy, for example, modify the preferred value, you must reset BGP sessions to apply the new policy. The reset operation tears down and re-establishes BGP sessions.
To avoid tearing down BGP sessions, you can use one of the following soft-reset methods to apply the new policy:
· Enabling route-refresh—The BGP router advertises a route-refresh message to the specified peer, and the peer resends its routing information to the router. After receiving the routing information, the router filters the routing information by using the new policy.
This method requires that both the local router and the peer support route refresh.
· Saving updates—Use the peer keep-all-routes command to save all route updates from the specified peer. After modifying the route selection policy, filter routing information by using the new policy.
This method does not require that the local router and the peer support route refresh but it uses more memory resources to save routes.
· Manual soft-reset—Use the refresh bgp command to enable BGP to send local routing information or advertise a route-refresh message to the specified peer. The peer then resends its routing information. After receiving the routing information, the router filters the routing information by using the new policy.
This method requires that both the local router and the peer support route refresh.
Enabling route-refresh
To enable BGP route refresh for a peer or peer group (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Enable BGP route refresh for a peer or peer group. |
·
Enable BGP route refresh for the
specified peer or peer group: ·
Enable the BGP route refresh,
multi-protocol extension, and 4-byte AS number features for the specified
peer or peer group: |
By default, the BGP route refresh, multi-protocol extension, and 4-byte AS number features are enabled. |
To enable BGP route refresh for a peer or peer group (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Enable BGP route refresh for a peer or peer group. |
·
Enable BGP route refresh for the
specified peer or peer group: ·
Enable the BGP route refresh,
multi-protocol extension, and 4-byte AS number features for the specified
peer or peer group: |
By default, the BGP route refresh, multi-protocol extension, and 4-byte AS number features are enabled. |
Saving updates
To save all route updates from the specified peer or peer group (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv4 unicast address family view, BGP-VPN IPv4 unicast address family view, or BGP IPv4 multicast address family view. |
· Enter BGP IPv4 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv4 [ unicast ] · Enter BGP-VPN IPv4 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv4 [ unicast ] · Enter BGP IPv4 multicast address family view: f. bgp as-number [ instance instance-name ] [ multi-session-thread ] g. address-family ipv4 multicast |
N/A |
3. Save all route updates from the peer or peer group. |
peer { group-name | ipv4-address [ mask-length ] } keep-all-routes |
By default, the routes are not saved. This command takes effect only for the routes received after this command is executed. |
To save all route updates from the specified peer or peer group (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv6 unicast address family view or BGP-VPN IPv6 unicast address family view. |
· Enter BGP IPv6 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv6 [ unicast ] · Enter BGP-VPN IPv6 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv6 [ unicast ] |
N/A |
3. Save all route updates from the peer or peer group. |
peer { group-name | ipv6-address [ prefix-length ] } keep-all-routes |
By default, the routes are not saved. This command takes effect only for the routes received after this command is executed. |
Configuring manual soft-reset
To configure manual soft-reset (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Enable BGP route refresh for a peer or peer group. |
·
Enable BGP route refresh for the
specified peer or peer group: ·
Enable the BGP route refresh, multi-protocol
extension, and 4-byte AS number features for the specified peer or peer
group: |
By default, the BGP route refresh, multi-protocol extension, and 4-byte AS number features are enabled. |
4. Return to user view. |
return |
N/A |
5. Perform manual soft-reset. |
refresh bgp [ instance instance-name ] { ipv4-address [ mask-length ] | all | external | group group-name | internal } { export | import } ipv4 { multicast | [ unicast ] [ vpn-instance vpn-instance-name ] } |
N/A |
To configure manual soft-reset (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Enable BGP route refresh for a peer or peer group. |
·
Enable BGP route refresh for the
specified peer or peer group: ·
Enable the BGP route refresh,
multi-protocol extension, and 4-byte AS number features for the specified
peer or peer group: |
By default, the BGP route refresh, multi-protocol extension, and 4-byte AS number features are enabled. |
4. Return to user view. |
return |
N/A |
5. Perform manual soft-reset. |
refresh bgp [ instance instance-name ] { ipv6-address [ prefix-length ] | all | external | group group-name | internal } { export | import } ipv6 unicast [ vpn-instance vpn-instance-name ] |
N/A |
To configure manual soft-reset (LS address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Enable BGP route refresh for a peer or peer group. |
·
Enable BGP route refresh for the specified
peer or peer group: ·
Enable the BGP route refresh, multi-protocol
extension, and 4-byte AS number features for the specified peer or peer
group: |
By default, the BGP route refresh, multi-protocol extension, and 4-byte AS number features are enabled. |
4. Return to user view. |
return |
N/A |
5. Perform manual soft-reset. |
refresh bgp [ instance instance-name ] { ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] | all | external | group group-name | internal } { export | import } link-state |
N/A |
Protecting an EBGP peer when memory usage reaches level 2 threshold
Memory usage includes the following threshold levels: normal, level 1, level 2, and level 3. When the level 2 threshold is reached, BGP periodically tears down an EBGP session to release memory resources until the memory usage falls below the level 2 threshold. You can configure this feature to avoid tearing down the EBGP session to an EBGP peer when the memory usage reaches the level 2 threshold.
For more information about memory usage thresholds, see Fundamentals Configuration Guide.
To configure BGP to protect an EBGP peer or peer group when the memory usage reaches level 2 threshold (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Configure BGP to protect an EBGP peer or peer group when the memory usage reaches level 2 threshold. |
peer { group-name | ipv4-address [ mask-length ] } low-memory-exempt |
By default, BGP periodically tears down an EBGP session to release memory resources when level 2 threshold is reached. |
To configure BGP to protect an EBGP peer or peer group when the memory usage reaches level 2 threshold (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Configure BGP to protect an EBGP peer or peer group when the memory usage reaches level 2 threshold. |
peer { group-name | ipv6-address [ prefix-length ] } low-memory-exempt |
By default, BGP tears down an EBGP session to release memory resources periodically when level 2 threshold is reached. |
Configuring an update delay for local MPLS labels
BGP includes local MPLS labels in advertised VPNv4 routes, VPNv6 routes, labeled IPv4 unicast routes, and labeled IPv6 unicast routes.
When a local label is changed, BGP removes the old label and advertises the new label. Traffic interruption occurs if BGP peers use the old label to forward packets before they learn the new label. To resolve this issue, configure an update delay for local MPLS labels. BGP does not remove the old label before the update delay timer expires.
To configure an update delay for local MPLS labels:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view. |
bgp as-number [ instance instance-name ] [ multi-session-thread ] |
N/A |
3. Configure an update delay for local MPLS labels. |
retain local-label retain-time |
By default, the update delay is 60 seconds. |
Flushing the suboptimal BGP route to the RIB
This feature flushes the suboptimal BGP route to the RIB when the following conditions are met:
· The optimal route is generated by the network command or is redistributed by the import-route command.
· The suboptimal route is received from a BGP peer.
After the suboptimal route is flushed to the RIB on a network, BGP immediately switches traffic to the suboptimal route when the optimal route fails.
For example, the device has a static route to the subnet 1.1.1.0/24 that has a higher priority than a BGP route. BGP redistributes the static route and receives a route to 1.1.1.0/24 from a peer. After the flush suboptimal-route command is executed, BGP flushes the received BGP route to the RIB as the suboptimal route. When the static route fails, BGP immediately switches traffic to the suboptimal route if inter-protocol FRR is enabled. For more information about inter-protocol FRR, see "Configuring basic IP routing."
To flush the suboptimal BGP route to the RIB:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP view. |
bgp as-number [ instance instance-name ] [ multi-session-thread ] |
N/A |
3. Flush the suboptimal BGP route to the RIB. |
flush suboptimal-route |
By default, BGP is disabled from flushing the suboptimal BGP route to the RIB, and only the optimal route is flushed to the RIB. |
Setting a DSCP value for outgoing BGP packets
The DSCP value of an IP packet specifies the priority level of the packet and affects the transmission priority of the packet.
To set a DSCP value for outgoing BGP packets:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Set a DSCP value for outgoing BGP packets. |
peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } dscp dscp-value |
By default, the DSCP value for outgoing BGP packets is 48. |
Enabling per-prefix label allocation
|
CAUTION: A change to the label allocation mode enables BGP to re-advertise all routes, which will cause service interruption. Use this command with caution. |
Perform this task to enable BGP to allocate a label to each route prefix.
To enable per-prefix label allocation:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view. |
bgp as-number [ instance instance-name ] [ multi-session-thread ] |
N/A |
3. Enable per-prefix label allocation. |
label-allocation-mode per-prefix |
By default, BGP allocates labels on a per-next-hop basis. |
Disabling optimal route selection for labeled routes without tunnel information
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view. |
bgp as-number [ instance instance-name ] [ multi-session-thread ] |
N/A |
3. Disable optimal route selection for labeled routes without tunnel information. |
labeled-route ignore-no-tunnel |
By default, labeled routes without tunnel information can participate in optimal route selection. |
Configuring a large-scale BGP network
In a large network, the number of BGP connections is huge and BGP configuration and maintenance are complicated. To simply BGP configuration, you can use the peer group, community, route reflector, and confederation features as needed. For more information about configuring peer groups, see "Configuring a BGP peer group."
Configuring BGP community
By default, a router does not advertise the COMMUNITY or extended community attribute to its peers or peer groups. When the router receives a route carrying the COMMUNITY or extended community attribute, it removes the attribute before advertising the route to other peers or peer groups.
Perform this task to enable a router to advertise the COMMUNITY or extended community attribute to its peers for route filtering and control. You can also use a routing policy to add or modify the COMMUNITY or extended community attribute for specific routes. For more information about routing policy, see "Configuring routing policies."
To configure BGP community (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv4 unicast address family view, BGP-VPN IPv4 unicast address family view, or BGP IPv4 multicast address family view. |
· Enter BGP IPv4 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv4 [ unicast ] · Enter BGP-VPN IPv4 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv4 [ unicast ] · Enter BGP IPv4 multicast address family view: f. bgp as-number [ instance instance-name ] [ multi-session-thread ] g. address-family ipv4 multicast |
N/A |
3. Advertise the COMMUNITY or extended community attribute to a peer or peer group. |
·
Advertise the COMMUNITY attribute to a
peer or peer group: ·
Advertise the extended community attribute to a
peer or peer group: |
By default, the COMMUNITY or extended community attribute is not advertised. |
4. (Optional.) Apply a routing policy to routes advertised to a peer or peer group. |
peer { group-name | ipv4-address [ mask-length ] } route-policy route-policy-name export |
By default, no routing policy is applied. |
To configure BGP community (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv6 unicast address family view or BGP-VPN IPv6 unicast address family view. |
· Enter BGP IPv6 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv6 [ unicast ] · Enter BGP-VPN IPv6 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv6 [ unicast ] |
N/A |
3. Advertise the COMMUNITY or extended community attribute to a peer or peer group. |
·
Advertise the COMMUNITY attribute to a
peer or peer group: ·
Advertise the extended community attribute to
a peer or peer group: |
By default, the COMMUNITY or extended community attribute is not advertised. |
4. (Optional.) Apply a routing policy to routes advertised to a peer or peer group. |
peer { group-name | ipv6-address [ prefix-length ] } route-policy route-policy-name export |
By default, no routing policy is applied. |
Configuring BGP route reflection
Configuring a BGP route reflector
Perform this task to configure a BGP route reflector and its clients. The route reflector and its clients automatically form a cluster identified by the router ID of the route reflector. The route reflector forwards route updates among its clients.
To improve availability, you can specify multiple route reflectors for a cluster. The route reflectors in the cluster must have the same cluster ID to avoid routing loops.
To configure a BGP route reflector (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv4 unicast address family view, BGP-VPN IPv4 unicast address family view, or BGP IPv4 multicast address family view. |
· Enter BGP IPv4 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv4 [ unicast ] · Enter BGP-VPN IPv4 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv4 [ unicast ] · Enter BGP IPv4 multicast address family view: f. bgp as-number [ instance instance-name ] [ multi-session-thread ] g. address-family ipv4 multicast |
N/A |
3. Configure the router as a route reflector and specify a peer or peer group as its client. |
peer { group-name | ipv4-address [ mask-length ] } reflect-client |
By default, no route reflector or client is configured. |
4. Enable route reflection between clients. |
reflect between-clients |
By default, route reflection between clients is enabled. |
5. (Optional.) Configure the cluster ID of the route reflector. |
reflector cluster-id { cluster-id | ipv4-address } |
By default, a route reflector uses its own router ID as the cluster ID. |
To configure a BGP route reflector (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv6 unicast address family view or BGP-VPN IPv6 unicast address family view. |
· Enter BGP IPv6 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv6 [ unicast ] · Enter BGP-VPN IPv6 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv6 [ unicast ] |
N/A |
3. Configure the router as a route reflector and specify a peer or peer group as its client. |
peer { group-name | ipv6-address [ prefix-length ] } reflect-client |
By default, no route reflector or client is configured. |
4. Enable route reflection between clients. |
reflect between-clients |
By default, route reflection between clients is enabled. |
5. (Optional.) Configure the cluster ID of the route reflector. |
reflector cluster-id { cluster-id | ipv4-address } |
By default, a route reflector uses its own router ID as the cluster ID. |
Ignoring the ORIGINATOR_ID attribute
By default, BGP drops incoming route updates whose ORIGINATOR_ID attribute is the same as the local router ID. Some special networks such as firewall networks require BGP to accept such route updates. To meet the requirement, you must configure BGP to ignore the ORIGINATOR_ID attribute.
To ignore the ORIGINATOR_ID attribute (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Ignore the ORIGINATOR_ID attribute. |
peer { group-name | ipv4-address [ mask-length ] } ignore-originatorid |
By default, BGP does not ignore the ORIGINATOR_ID attribute. Make sure this command does not result in a routing loop. After you execute this command, BGP also ignores the CLUSTER_LIST attribute. |
To ignore the ORIGINATOR_ID attribute (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Ignore the ORIGINATOR_ID attribute. |
peer { group-name | ipv6-address [ prefix-length ] } ignore-originatorid |
By default, BGP does not ignore the ORIGINATOR_ID attribute. Make sure this command does not result in a routing loop. After you execute this command, BGP also ignores the CLUSTER_LIST attribute. |
Configuring a BGP confederation
BGP confederation provides another way to reduce IBGP connections in an AS.
A confederation contains sub-ASs. In each sub-AS, IBGP peers are fully meshed. Sub-ASs establish EBGP connections in between.
Configuring a BGP confederation
After you split an AS into multiple sub-ASs, configure a router in a sub-AS as follows:
1. Enable BGP and specify the AS number of the router. For more information, see "Enabling BGP."
2. Specify the confederation ID. From an outsider's perspective, the sub-ASs of the confederation is a single AS, which is identified by the confederation ID.
3. If the router needs to establish EBGP connections to other sub-ASs, you must specify the peering sub-ASs in the confederation.
A confederation can contain a maximum of 32 sub-ASs. The AS number of a sub-AS is effective only in the confederation.
To configure a BGP confederation:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view. |
bgp as-number [ instance instance-name ] [ multi-session-thread ] |
N/A |
3. Configure a confederation ID. |
confederation id as-number |
By default, no confederation ID is configured. |
4. Specify confederation peer sub-ASs in the confederation. |
confederation peer-as as-number-list |
By default, no confederation peer sub-ASs are specified. |
Configuring confederation compatibility
If any routers in the confederation do not comply with RFC 3065, enable confederation compatibility to allow the router to work with those routers.
To configure confederation compatibility:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view. |
bgp as-number [ instance instance-name ] [ multi-session-thread ] |
N/A |
3. Enable confederation compatibility. |
confederation nonstandard |
By default, confederation compatibility is disabled. |
Configuring BGP GR
Graceful Restart (GR) ensures forwarding continuous when a routing protocol restarts or an active/standby switchover occurs. Two routers are required to complete a GR process. The following are router roles in a GR process:
· GR restarter—Performs GR upon a BGP restart or active/standby switchover.
· GR helper—Helps the GR restarter to complete the GR process.
A device can act as a GR restarter and GR helper at the same time.
BGP GR works as follows:
1. The BGP GR restarter and helper exchange Open messages for GR capability negotiation. If both parties have the GR capability, they establish a GR-capable session. The GR restarter sends the GR timer set by the graceful-restart timer restart command to the GR helper in an Open message.
2. When an active/standby switchover occurs or BGP restarts, the GR restarter does not remove existing BGP routes from Routing Information Base (RIB) and Forwarding Information Base (FIB). It still uses these routes for packet forwarding, and it starts the RIB purge timer (set by the graceful-restart timer purge-time command). The GR helper marks all routes learned from the GR restarter as stale instead of deleting them. It continues to use these routes for packet forwarding. During the GR process, packet forwarding is not interrupted.
3. After the active/standby switchover or BGP restart completes, the GR restarter re-establishes a BGP session to the GR helper. If the BGP session fails to be established within the GR timer advertised by the GR restarter, the GR helper removes the stale routes.
4. If the BGP session is established, routing information is exchanged for the GR restarter to retrieve route entries and for the GR helper to recover stale routes.
5. Both the GR restarter and the GR helper start the End-Of-RIB marker waiting timer.
The End-Of-RIB marker waiting time is set by the graceful-restart timer wait-for-rib command. If routing information exchange is not completed within the time, the GR restarter does not receive new routes. The GR restarter updates the RIB with the BGP routes already learned, and removes the aged routes from the RIB. The GR helper removes the stale routes.
6. The GR restarter quits the GR process if routing information exchange is not completed within the RIB purge timer. It updates the RIB with the BGP routes already learned, and removes the aged routes.
Follow these guidelines when you configure BGP GR:
· The End-Of-RIB indicates the end of route updates.
· The maximum time to wait for the End-of-RIB marker configured on the local end is not advertised to the peer. It controls the time for the local end to receive updates from the peer.
As a best practice, perform the following configuration on the GR restarter and GR helper.
To configure BGP GR:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view. |
bgp as-number [ instance instance-name ] [ multi-session-thread ] |
N/A |
3. Enable GR capability for BGP. |
graceful-restart |
By default, GR capability is disabled for BGP. |
4. Configure the GR timer. |
graceful-restart timer restart timer |
The default setting is 150 seconds. The time that a peer waits to re-establish a session must be less than the hold time. |
5. Configure the maximum time to wait for the End-of-RIB marker. |
graceful-restart timer wait-for-rib timer |
The default setting is 180 seconds. |
6. Configure the RIB purge timer. |
graceful-restart timer purge-time timer |
The default setting is 480 seconds. |
Configuring BGP NSR
To use BGP nonstop routing (NSR), the system must have a minimum of two MPUs or two IRF member devices.
NSR ensures nonstop services when BGP has redundant processes on multiple MPUs or IRF member devices. In contrast to GR, NSR does not require a neighbor device to recover routing information.
BGP NSR backs up BGP state and data information from the active BGP process to the standby BGP process. The standby BGP process takes over when any of the following events occurs:
· The active BGP process restarts.
· The MPU/IRF member device that runs the active BGP process fails.
· An ISSU starts on the MPU/IRF member device that runs the active BGP process.
When both GR and NSR are configured for BGP, NSR has a higher priority than GR. The device will not act as the GR restarter. If the device acts as a GR helper, it cannot help the restarter to complete GR.
To use BGP NSR in MPLS L3VPN, you must enable RIB NSR. For information about RIB NSR, see "Configuring basic IP routing."
To configure BGP NSR:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view. |
bgp as-number [ instance instance-name ] [ multi-session-thread ] |
N/A |
3. Enable BGP NSR. |
non-stop-routing |
By default, BGP NSR is disabled. |
Enabling SNMP notifications for BGP
After you enable SNMP notifications for BGP, the device generates a notification when a BGP neighbor state change occurs. The notification includes the neighbor address, the error code and subcode of the most recent error, and the current neighbor state.
For BGP notifications to be sent correctly, you must also configure SNMP on the device. For more information about SNMP configuration, see the network management and monitoring configuration guide for the device.
To enable SNMP notifications for BGP:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enable SNMP notifications for BGP. |
snmp-agent trap enable bgp [ instance instance-name ] |
By default, SNMP notifications for BGP are enabled. |
Enabling logging for session state changes
Perform this task to enable BGP to log BGP session establishment and disconnection events. To display the log information, use the display bgp peer ipv4 unicast log-info command or the display bgp peer ipv6 unicast log-info command. The logs are sent to the information center. The output rules of the logs (whether to output the logs and where to output) are determined by the information center configuration.
For more information about information center configuration, see Network Management and Monitoring Configuration Guide.
To enable logging for session state changes (IPv4 unicast/IPv4 multicast):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view. |
bgp as-number [ instance instance-name ] [ multi-session-thread ] |
N/A |
3. Enable logging for session state changes globally. |
log-peer-change |
By default, logging for session state changes is enabled globally. |
4. (Optional.) Enter BGP-VPN instance view. |
ip vpn-instance vpn-instance-name |
N/A |
5. Enable logging for session state changes for a peer or peer group. |
peer { group-name | ipv4-address [ mask-length ] } log-change |
By default, logging for session state changes is enabled for all peers or peer groups. |
To enable logging for session state changes (IPv6 unicast):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view. |
bgp as-number [ instance instance-name ] [ multi-session-thread ] |
N/A |
3. Enable logging for session state changes globally. |
log-peer-change |
By default, logging for session state changes is enabled globally. |
4. (Optional.) Enter BGP-VPN instance view. |
ip vpn-instance vpn-instance-name |
N/A |
5. Enable logging for session state changes for a peer or peer group. |
peer { group-name | ipv6-address [ prefix-length ] } log-change |
By default, logging for session state changes is enabled for all peers or peer groups. |
Enabling logging for BGP route flapping
This feature enables BGP to generate logs for BGP route flappings that trigger log generation. The generated logs are sent to the information center. For the logs to be output correctly, you must also configure information center on the device. For more information about the information center, see Network Management and Monitoring Configuration Guide.
To enable logging for BGP route flapping (IPv4 unicast/IPv4 multicast):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv4 unicast address family view, BGP-VPN IPv4 unicast address family view, or BGP IPv4 multicast address family view. |
· Enter BGP IPv4 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv4 [ unicast ] · Enter BGP-VPN IPv4 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv4 [ unicast ] · Enter BGP IPv4 multicast address family view: f. bgp as-number [ instance instance-name ] [ multi-session-thread ] g. address-family ipv4 multicast |
N/A |
3. Enable logging for BGP route flapping. |
log-route-flap monitor-time monitor-count [ log-count-limit | route-policy route-policy-name ] * |
By default, logging for BGP route flapping is disabled. |
To enable logging for BGP route flapping (IPv6 unicast):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP IPv6 unicast address family view or BGP-VPN IPv6 unicast address family view. |
· Enter BGP IPv6 unicast address family view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. address-family ipv6 [ unicast ] · Enter BGP-VPN IPv6 unicast address family view: c. bgp as-number [ instance instance-name ] [ multi-session-thread ] d. ip vpn-instance vpn-instance-name e. address-family ipv6 [ unicast ] |
N/A |
3. Enable logging for BGP route flapping. |
log-route-flap monitor-time monitor-count [ log-count-limit | route-policy route-policy-name ] * |
By default, logging for BGP route flapping is disabled. |
Configuring BFD for BGP
|
IMPORTANT: If you have enabled GR, use BFD with caution because BFD might detect a failure before the system performs GR, which will result in GR failure. If you have enabled both BFD and GR for BGP, do not disable BFD during a GR process to avoid GR failure. |
BGP maintains neighbor relationships based on the keepalive timer and hold timer in seconds. It requires that the hold time must be at least three times the keepalive interval. This mechanism slows down link failure detection. Once a failure occurs on a high-speed link, a large quantity of packets will be dropped before routing convergence completes. BFD for BGP can solve this problem by fast detecting link failures to reduce convergence time.
Before you enable BFD for a BGP peer or peer group, you must establish a BGP session between the local router and the peer or peer group.
For more information about BFD, see High Availability Configuration Guide.
To enable BFD for a BGP peer (IPv4 unicast/multicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Enable BFD to detect the link to the specified BGP peer or peer group. |
peer { group-name | ipv4-address [ mask-length ] } bfd [ multi-hop | single-hop ] |
By default, BFD is disabled. |
To enable BFD for a BGP peer (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
3. Enable BFD to detect the link to the specified IPv6 BGP peer or peer group. |
peer { group-name | ipv6-address [ prefix-length ] } bfd [ multi-hop | single-hop ] |
By default, BFD is disabled. |
Configuring BGP FRR
When a link fails, the packets on the link are discarded, and a routing loop might occur until BGP completes routing convergence based on the new network topology.
You can enable BGP fast reroute (FRR) to resolve this issue.
Figure 63 Network diagram for BGP FRR
After you configure FRR on Router B as shown in Figure 63, BGP generates a backup next hop Router C for the primary route. BGP uses ARP (for IPv4), echo-mode BFD (for IPv4), or ND (for IPv6) to detect the connectivity to Router D. When the link to Router D fails, BGP directs packets to the backup next hop. At the same time, BGP calculates a new optimal route, and forwards packets over the optimal route.
You can use the following methods to configure BGP FRR:
· Method 1—Execute the pic command in BGP address family view. BGP calculates a backup next hop for each BGP route in the address family if there are two or more unequal-cost routes that reach the destination.
· Method 2—Execute the fast-reroute route-policy command to use a routing policy in which a backup next hop is specified by using the command apply [ ipv6 ] fast-reroute backup-nexthop. The backup next hop calculated by BGP must be the same as the specified backup next hop. Otherwise, BGP does not generate a backup next hop for the primary route. You can also configure if-match clauses in the routing policy to identify the routes protected by FRR.
If both methods are configured, Method 2 takes precedence over Method 1.
BGP supports FRR for IPv4 and IPv6 unicast routes, but not for IPv4 multicast routes.
To configure BGP FRR (IPv4 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Configure the source address of echo packets. |
bfd echo-source-ip ipv4-address |
By default, no source address is specified for echo packets. This step is required when echo-mode BFD is used to detect the connectivity to the next hop of the primary route. Specify a source IP address that does not belong to any local network. For more information about this command, see High Availability Command Reference. |
3. Create a routing policy and enter routing policy view. |
route-policy route-policy-name permit node node-number |
By default, no routing policies exist. This step is required when Method 2 is used to enable BGP FRR. For more information about this command, see Layer 3—IP Routing Command Reference. |
4. Set the backup next hop for FRR. |
apply fast-reroute backup-nexthop ipv4-address |
By default, no backup next hop is set. This step is required when Method 2 is used to enable BGP FRR. For more information about this command, see Layer 3—IP Routing Command Reference. |
5. Return to system view. |
quit |
N/A |
6. Enter BGP instance view. |
bgp as-number [ instance instance-name ] [ multi-session-thread ] |
N/A |
7. (Optional.) Use echo-mode BFD to detect the connectivity to the next hop of the primary route. |
primary-path-detect bfd echo |
By default, ARP is used to detect the connectivity to the next hop. |
8. (Optional.) Enter BGP-VPN instance view. |
ip vpn-instance vpn-instance-name |
N/A |
9. Enter BGP IPv4 unicast address family view or BGP-VPN IPv4 unicast address family view. |
address-family ipv4 [ unicast ] |
N/A |
10. Enable BGP FRR. |
·
(Method 1) Enable BGP FRR for the address
family: ·
(Method 2) Apply a routing policy to FRR
for the address family: |
By default, BGP FRR is disabled. Method 1 might result in routing loops. Use it with caution. By default, no routing policy is applied. The apply fast-reroute backup-nexthop and apply ipv6 fast-reroute backup-nexthop commands can take effect in the applied routing policy. Other apply commands do not take effect. |
To configure BGP FRR (IPv6 unicast address family):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Create a routing policy and enter routing policy view. |
route-policy route-policy-name permit node node-number |
By default, no routing policies exist. This step is required when Method 2 is used to enable BGP FRR. For more information about this command, see Layer 3—IP Routing Command Reference. |
3. Set the backup next hop for FRR. |
apply ipv6 fast-reroute backup-nexthop ipv6-address |
By default, no backup next hop is set. This step is required when Method 2 is used to enable BGP FRR. For more information about this command, see Layer 3—IP Routing Command Reference. |
4. Return to system view. |
quit |
N/A |
5. Enter BGP instance view or BGP-VPN instance view. |
·
Enter BGP instance view: · Enter BGP-VPN instance view: a. bgp as-number [ instance instance-name ] [ multi-session-thread ] b. ip vpn-instance vpn-instance-name |
N/A |
6. Enter BGP IPv6 unicast address family view or BGP-VPN IPv6 unicast address family view. |
address-family ipv6 [ unicast ] |
N/A |
7. Enable BGP FRR. |
·
(Method 1) Enable BGP FRR for the address
family: ·
(Method 2) Apply a routing policy to
FRR for the address family: |
By default, BGP FRR is disabled. Method 1 might result in routing loops. Use it with caution. By default, no routing policy is applied. The apply fast-reroute backup-nexthop and apply ipv6 fast-reroute backup-nexthop commands can take effect in the applied routing policy. Other apply commands do not take effect. |
Configuring 6PE
IPv6 provider edge (6PE) is a transition technology that uses MPLS to connect sparsely populated IPv6 networks through an existing IPv4 backbone network. It is an efficient solution for ISP IPv4/MPLS networks to provide IPv6 traffic switching capability.
Figure 64 Network diagram for 6PE
6PE mainly performs the following operations:
· 6PE assigns a label to IPv6 routing information received from a CE router, and sends the labeled IPv6 routing information to the peer 6PE device through an MP-BGP session. The peer 6PE device then forwards the IPv6 routing information to the attached customer site.
· 6PE provides tunnels over the IPv4 backbone so the IPv4 backbone can forward packets for IPv6 networks. The tunnels can be GRE tunnels, MPLS LSPs, or MPLS TE tunnels.
· Upon receiving an IPv6 packet, 6PE adds an inner tag (corresponding to the IPv6 packet) and then an outer tag (corresponding to the public network tunnel) to the IPv6 packet. Devices in the IPv4 backbone network forwards the packet based on the outer tag. When the peer 6PE device receives the packet, it removes the outer and inner tags and forwards the original IPv6 packet to the attached customer site.
To implement exchange of IPv6 routing information, you can configure IPv6 static routing, an IPv6 IGP protocol, or IPv6 BGP between CE and 6PE devices.
For more information about MPLS, MPLS TE, CE, and P, see MPLS Configuration Guide. For more information about GRE, see Layer 3—IP Services Configuration Guide.
Configuring basic 6PE
Before you configure 6PE, perform the following tasks:
· Establish tunnels in the IPv4 backbone network (see Layer 3—IP Services Configuration Guide).
· Configure basic MPLS on 6PE devices (see MPLS Configuration Guide).
· Configure BGP on 6PE devices so that they can advertise tagged IPv6 routing information through BGP sessions. The following describes only BGP configurations on 6PE devices.
To configure basic 6PE:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view. |
bgp as-number [ instance instance-name ] [ multi-session-thread ] |
N/A |
3. Specify a 6PE peer or peer group and its AS number. |
peer { group-name | ipv4-address [ mask-length ] } as-number as-number |
No 6PE peer is specified by default. |
4. Enter BGP IPv6 unicast address family view. |
address-family ipv6 [ unicast ] |
N/A |
5. Enable BGP to exchange IPv6 unicast routing information with the 6PE peer or peer group. |
peer { group-name | ipv4-address [ mask-length ] } enable |
This feature is disabled by default. |
6. Enable BGP to exchange labeled IPv6 routes with the 6PE peer or peer group. |
peer { group-name | ipv4-address [ mask-length ] } label-route-capability |
This feature is disabled by default. |
Configuring optional 6PE capabilities
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view. |
bgp as-number [ instance instance-name ] [ multi-session-thread ] |
N/A |
3. Enter BGP IPv6 unicast address family view. |
address-family ipv6 [ unicast ] |
N/A |
4. Advertise COMMUNITY attribute to the 6PE peer or peer group. |
peer { group-name | ipv4-address [ mask-length ] } advertise-community |
By default, the COMMUNITY attribute is not advertised. |
5. Advertise extended community attribute to the 6PE peer or peer group. |
peer { group-name | ipv4-address [ mask-length ] } advertise-ext-community |
By default, the extended community attribute is not advertised. |
6. Allow the local AS number to appear in routes from the 6PE peer or peer group and specify the repeat times. |
peer { group-name | ipv4-address [ mask-length ] } allow-as-loop [ number ] |
By default, the local AS number is not allowed to appear in routes from the 6PE peer or peer group. |
7. Specify an AS path list to filter routes advertised to or received from the 6PE peer or peer group. |
peer { group-name | ipv4-address [ mask-length ] } as-path-acl as-path-acl-number { export | import } |
By default, no AS path list is specified. |
8. Specify an IPv6 ACL to filter routes advertised to or received from the 6PE peer or peer group. |
peer { group-name | ipv4-address [ mask-length ] } filter-policy ipv6-acl-number { export | import } |
By default, no ACL is specified. |
9. Specify an IPv6 prefix list to filter routes advertised to or received from the 6PE peer or peer group. |
peer { group-name | ipv4-address [ mask-length ] } prefix-list ipv6-prefix-name { export | import } |
By default, no IPv6 prefix list is specified. |
10. Specify a routing policy to filter routes advertised to or received from the 6PE peer or peer group. |
peer { group-name | ipv4-address [ mask-length ] } route-policy route-policy-name { export | import } |
By default, no routing policy is specified. |
11. Advertise a default route to the 6PE peer or peer group. |
peer { group-name | ipv4-address [ mask-length ] } default-route-advertise [ route-policy route-policy-name ] |
By default, no default route is advertised. |
12. Save all routes from the 6PE peer or peer group. |
peer { group-name | ipv4-address [ mask-length ] } keep-all-routes |
By default, routes from a peer or peer group are not saved. |
13. Configure BGP updates sent to the 6PE peer or peer group to carry only public AS numbers. |
peer { group-name | ipv4-address [ mask-length ] } public-as-only |
By default, BGP updates sent to a 6PE peer or peer group can carry both public and private AS numbers. |
14. Specify the maximum number of routes that BGP can receive from the 6PE peer or peer group. |
peer { group-name | ipv4-address [ mask-length ] } route-limit prefix-number [ { alert-only discard | reconnect reconnect-time } | percentage-value ] * |
By default, the number of routes that a router can receive from the 6PE peer or peer group is not limited. |
15. Specify a preferred value for routes received from the 6PE peer or peer group. |
peer { group-name | ipv4-address [ mask-length ] } preferred-value value |
By default, the preferred value is 0. |
16. Configure the device as a route reflector and the 6PE peer or peer group as a client. |
peer { group-name | ipv4-address [ mask-length ] } reflect-client |
By default, no route reflector or client is configured. |
17. Configure the SoO attribute for a peer or peer group. |
peer { group-name | ipv4-address [ mask-length ] } soo site-of-origin |
By default, no SoO attribute is configured for a peer or peer group. |
18. Return to user view. |
return |
N/A |
19. Display information about the 6PE peer or peer group. |
display bgp [ instance instance-name ] peer ipv6 [ unicast ] [ ipv4-address mask-length | { ipv4-address | group-name group-name } log-info | [ ipv4-address ] verbose ] |
Available in any view. |
20. Display routing information advertised to or received from the 6PE peer or peer group. |
display bgp [ instance instance-name ] routing-table ipv6 [ unicast ] peer ipv4-address { advertised-routes | received-routes } [ ipv6-address prefix-length | statistics ] |
Available in any view. |
21. Soft-reset a BGP 6PE connection. |
refresh bgp [ instance instance-name ] ipv4-address [ mask-length ] { export | import } ipv6 [ unicast ] |
Available in user view. |
22. Reset a BGP 6PE connection. |
reset bgp [ instance instance-name ] ipv4-address [ mask-length ] ipv6 [ unicast ] |
Available in user view. |
Configuring BGP LS
The BGP Link State (LS) feature implements inter-domain and inter-AS advertisement of link state database (LSDB) and TE database (TEDB) information.
The device sends the collected link state information to the controller, which implements end-to-end traffic management and scheduling, and meets the requirements of intended applications.
Configuring basic BGP LS
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view. |
bgp as-number [ instance instance-name ] [ multi-session-thread ] |
N/A |
3. Specify an AS number for an LS peer or peer group. |
peer { ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } as-number as-number peer group-name as-number as-number |
By default, no AS number is specified. |
4. Create the BGP LS address family and enter its view. |
address-family link-state |
N/A |
5. Enable the device to exchange LS information with the peer or peer group. |
peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } enable |
By default, the device cannot exchange LS information with the peer or peer group. |
Configuring BGP LS route reflection
Perform this task to configure a BGP route reflector and its clients. The route reflector and its clients automatically form a cluster identified by the router ID of the route reflector. The route reflector forwards route updates among its clients.
To configure BGP LS route reflection:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view. |
bgp as-number [ instance instance-name ] [ multi-session-thread ] |
N/A |
3. Enter BGP LS address family view. |
address-family link-state |
N/A |
4. Configure the device as a route reflector and specify a peer or peer group as its client. |
peer { group-name | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] } reflect-client |
By default, no route reflector or client is configured. |
5. Enable route reflection between clients. |
reflect between-clients |
By default, route reflection between clients is enabled. |
6. (Optional.) Configure the cluster ID of the route reflector. |
reflector cluster-id { cluster-id | ipv4-address } |
By default, a route reflector uses its own router ID as the cluster ID. |
Specifying an AS number and a router ID for BGP LS messages
Perform this task to ensure that LS messages sent by devices in the same AS have the same AS number and router ID.
To specify an AS number and a router ID for BGP LS messages:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter BGP instance view. |
bgp as-number [ instance instance-name ] [ multi-session-thread ] |
N/A |
3. Enter BGP LS address family view. |
address-family link-state |
N/A |
4. Specify an AS number and a router ID for BGP LS messages. |
domain-distinguisher as-number:router-id |
By default, the AS number and router ID of the current BGP process are used. |
Displaying and maintaining BGP
Displaying BGP
Execute display commands in any view (IPv4 unicast address family).
Task |
Command |
|
Display BGP NSR status information. |
display bgp [ instance instance-name ] non-stop-routing status |
|
Display BGP IPv4 unicast peer group information. |
display bgp [ instance instance-name ] group ipv4 [ unicast ] [ vpn-instance vpn-instance-name ] [ group-name group-name ] |
|
Display BGP IPv4 unicast peer or peer group information. |
display bgp [ instance instance-name ] peer ipv4 [ unicast ] [ vpn-instance vpn-instance-name ] [ ipv4-address mask-length | { ipv4-address | group-name group-name } log-info | [ ipv4-address ] verbose ] |
|
Display BGP IPv4 unicast routing information. |
display bgp [ instance instance-name ] routing-table ipv4 [ unicast ] [ vpn-instance vpn-instance-name ] [ ipv4-address [ { mask-length | mask } [ longest-match ] ] | ipv4-address [ mask-length | mask ] advertise-info | as-path-acl as-path-acl-number | community-list { { basic-community-list-number | comm-list-name } [ whole-match ] | adv-community-list-number } | peer ipv4-address { advertised-routes | received-routes } [ ipv4-address [ mask-length | mask ] | statistics ] | statistics ] |
|
Display dampened BGP IPv4 unicast routing information. |
display bgp [ instance instance-name ] routing-table dampened ipv4 [ unicast ] [ vpn-instance vpn-instance-name ] |
|
Display BGP dampening parameter information. |
display bgp [ instance instance-name ] dampening parameter ipv4 [ unicast ] [ vpn-instance vpn-instance-name ] |
|
Display BGP IPv4 unicast routing flap statistics. |
display bgp [ instance instance-name ] routing-table flap-info ipv4 [ unicast ] [ vpn-instance vpn-instance-name ] [ ipv4-address [ { mask-length | mask } [ longest-match ] ] | as-path-acl as-path-acl-number ] |
|
Display information about routes advertised by the network command and shortcut routes configured by the network short-cut command. |
display bgp [ instance instance-name ] network ipv4 [ unicast ] [ vpn-instance vpn-instance-name ] |
|
Display BGP path attribute information. |
display bgp [ instance instance-name ] paths [ as-regular-expression ] |
|
Display BGP IPv4 unicast address family update group information. |
display bgp [ instance instance-name ] update-group ipv4 [ unicast ] [ vpn-instance vpn-instance-name ] [ ipv4-address ] |
|
Display information about all BGP instances. |
display bgp instance-info |
|
Execute display commands in any view (IPv6 unicast address family).
Task |
Command |
|
Display BGP NSR status information. |
display bgp [ instance instance-name ] non-stop-routing status |
|
Display BGP IPv6 unicast peer group information. |
display bgp [ instance instance-name ] group ipv6 [ unicast ] [ vpn-instance vpn-instance-name ] [ group-name group-name ] |
|
Display BGP IPv6 unicast peer or peer group information. |
display bgp [ instance instance-name ] peer ipv6 [ unicast ] [ vpn-instance vpn-instance-name ] [ ipv6-address prefix-length | { ipv6-address | group-name group-name } log-info | [ ipv6-address ] verbose ] display bgp [ instance instance-name ] peer ipv6 [ unicast ] [ ipv4-address mask-length | ipv4-address log-info | [ ipv4-address ] verbose ] |
|
Display BGP IPv6 unicast routing information. |
display bgp [ instance instance-name ] routing-table ipv6 [ unicast ] [ vpn-instance vpn-instance-name ] [ ipv6-address prefix-length [ advertise-info ] | as-path-acl as-path-acl-number | community-list { { basic-community-list-number | comm-list-name } [ whole-match ] | adv-community-list-number } | peer ipv6-address { advertised-routes | received-routes } [ ipv6-address prefix-length | statistics ] | statistics ] display bgp [ instance instance-name ] routing-table ipv6 [ unicast ] peer ipv4-address { advertised-routes | received-routes } [ ipv6-address prefix-length | statistics ] |
|
Display dampened BGP IPv6 unicast routing information. |
display bgp [ instance instance-name ] routing-table dampened ipv6 [ unicast ] [ vpn-instance vpn-instance-name ] |
|
Display BGP dampening parameter information. |
display bgp [ instance instance-name ] dampening parameter ipv6 [ unicast ] [ vpn-instance vpn-instance-name ] |
|
Display BGP IPv6 unicast routing flap statistics. |
display bgp [ instance instance-name ] routing-table flap-info ipv6 [ unicast ] [ vpn-instance vpn-instance-name ] [ ipv6-address prefix-length | as-path-acl as-path-acl-number ] |
|
Display incoming labels for BGP IPv6 unicast routes. |
display bgp [ instance instance-name ] routing-table ipv6 [ unicast ] inlabel |
|
Display outgoing labels of BGP IPv6 unicast routes. |
display bgp [ instance instance-name ] routing-table ipv6 [ unicast ] outlabel |
|
Display information about routes advertised by the network command and shortcut routes configured by the network short-cut command. |
display bgp [ instance instance-name ] network ipv6 [ unicast ] [ vpn-instance vpn-instance-name ] |
|
Display BGP path attribute information. |
display bgp [ instance instance-name ] paths [ as-regular-expression ] |
|
Display BGP IPv6 unicast address family update group information. |
display bgp [ instance instance-name ] update-group ipv6 [ unicast ] [ ipv4-address | ipv6-address ] display bgp [ instance instance-name ] update-group ipv6 [ unicast ] vpn-instance vpn-instance-name [ ipv6-address ] |
|
Display information about all BGP instances. |
display bgp instance-info |
|
Execute display commands in any view (IPv4 multicast address family).
Task |
Command |
|
Display BGP NSR status information. |
display bgp [ instance instance-name ] non-stop-routing status |
|
Display BGP IPv4 multicast peer group information. |
display bgp [ instance instance-name ] group ipv4 multicast [ group-name group-name ] |
|
Display BGP IPv4 multicast peer or peer group information. |
display bgp [ instance instance-name ] peer ipv4 multicast [ ipv4-address mask-length | { ipv4-address | group-name group-name } log-info | [ ipv4-address ] verbose ] |
|
Display BGP IPv4 multicast routing information. |
display bgp [ instance instance-name ] routing-table ipv4 multicast [ ipv4-address [ { mask-length | mask } [ longest-match ] ] | ipv4-address [ mask-length | mask ] advertise-info | as-path-acl as-path-acl-number | community-list { { basic-community-list-number | comm-list-name } [ whole-match ] | adv-community-list-number } | peer ipv4-address { advertised-routes | received-routes } [ ipv4-address [ mask-length | mask ] | statistics ] | statistics ] |
|
Display dampened BGP IPv4 multicast routing information. |
display bgp [ instance instance-name ] routing-table dampened ipv4 multicast |
|
Display BGP dampening parameter information. |
display bgp [ instance instance-name ] dampening parameter ipv4 multicast |
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Display BGP IPv4 multicast routing flap statistics. |
display bgp [ instance instance-name ] routing-table flap-info ipv4 multicast [ ipv4-address [ { mask-length | mask } [ longest-match ] ] | as-path-acl as-path-acl-number ] |
|
Display information about routes advertised by the network command and shortcut routes configured by the network short-cut command. |
display bgp [ instance instance-name ] network ipv4 multicast |
|
Display BGP path attribute information. |
display bgp [ instance instance-name ] paths [ as-regular-expression ] |
|
Display BGP IPv4 multicast address family update group information. |
display bgp [ instance instance-name ] update-group ipv4 multicast [ ipv4-address ] |
|
Display information about all BGP instances. |
display bgp instance-info |
|
Execute display commands in any view (LS address family).
Task |
Command |
Display BGP LS peer group information. |
display bgp [ instance instance-name ] group link-state [ group-name group-name ] |
Display BGP LS information. |
display bgp [ instance instance-name ] link-state [ ls-prefix ] { advertise-info | statistics } [ peer { ipv4-address | ipv6-address } { advertised | received } statistics ] |
Display BGP LS peer or peer group information. |
display bgp [ instance instance-name ] peer link-state [ ipv4-address mask-length | ipv6-address prefix-length | { ipv4-address | ipv6-address | group-name group-name } log-info | [ ipv4-address | ipv6-address ] verbose ] |
Display BGP LS address family update group information. |
display bgp [ instance instance-name ] update-group link-state [ ipv4-address | ipv6-address ] |
Resetting BGP sessions
Execute reset commands in user view.
Task |
Command |
Reset all BGP sessions. |
reset bgp [ instance instance-name ] all |
Reset BGP sessions for IPv4 unicast address family. |
reset bgp [ instance instance-name ] { as-number | ipv4-address [ mask-length ] | all | external | group group-name | internal } ipv4 [ unicast ] [ vpn-instance vpn-instance-name ] |
Reset BGP sessions for IPv6 unicast address family. |
reset bgp [ instance instance-name ] { as-number | ipv6-address [ prefix-length ] | all | external | group group-name | internal } ipv6 [ unicast ] [ vpn-instance vpn-instance-name ] reset bgp [ instance instance-name ] ipv4-address [ mask-length ] ipv6 [ unicast ] |
Reset BGP sessions for LS address family. |
reset bgp [ instance instance-name ] { as-number | ipv4-address [ mask-length ] | ipv6-address [ prefix-length ] | all | external | group group-name | internal } { export | import } link-state |
Reset BGP sessions for IPv4 multicast address family. |
reset bgp [ instance instance-name ] { as-number | ipv4-address [ mask-length ] | all | external | group group-name | internal } ipv4 multicast |
Clearing BGP information
Execute reset commands in user view.
Task |
Command |
Clear dampening information for BGP IPv4 unicast routes and release suppressed BGP IPv4 unicast routes. |
reset bgp [ instance instance-name ] dampening ipv4 [ unicast ] [ vpn-instance vpn-instance-name ] [ ipv4-address [ mask-length | mask ] ] |
Clear flap information for BGP IPv4 unicast routes. |
reset bgp [ instance instance-name ] flap-info ipv4 [ unicast ] [ vpn-instance vpn-instance-name ] [ ipv4-address [ mask-length | mask ] | as-path-acl as-path-acl-number | peer ipv4-address [ mask-length ] ] |
Clear dampening information for BGP IPv6 unicast routes and release suppressed BGP IPv6 unicast routes. |
reset bgp [ instance instance-name ] dampening ipv6 [ unicast ] [ vpn-instance vpn-instance-name ] [ ipv6-address prefix-length ] |
Clear flap information for BGP IPv6 unicast routes. |
reset bgp [ instance instance-name ] flap-info ipv6 [ unicast ] [ vpn-instance vpn-instance-name ] [ ipv6-address prefix-length | as-path-acl as-path-acl-number | peer ipv6-address [ prefix-length ] ] |
Clear dampening information for BGP IPv4 multicast routes and release suppressed BGP IPv4 multicast routes. |
reset bgp [ instance instance-name ] dampening ipv4 multicast [ ipv4-address [ mask-length | mask] ] |
Clear flap information for BGP IPv4 multicast routes. |
reset bgp [ instance instance-name ] flap-info ipv4 multicast [ ipv4-address [ mask-length | mask ] | as-path-acl as-path-acl-number | peer ipv4-address [ mask-length ] ] |
IPv4 BGP configuration examples
Basic BGP configuration example
Network requirements
As shown in Figure 65, all switches run BGP. Run EBGP between Switch A and Switch B, and run IBGP between Switch B and Switch C to allow Switch C to access network 8.1.1.0/24 connected to Switch A.
Requirements analysis
To prevent route flapping caused by port state changes, this example uses loopback interfaces to establish IBGP connections. Loopback interfaces are virtual interfaces. Therefore, use the peer connect-interface command to specify the loopback interface as the source interface for establishing BGP connections. Enable OSPF in AS 65009 to ensure that Switch B can communicate with Switch C through loopback interfaces.
The EBGP peers, Switch A and Switch B (usually belong to different carriers), are located in different ASs. Typically, their loopback interfaces are not reachable to each other, so directly connected interfaces are used for establishing EBGP sessions. To enable Switch C to access the network 8.1.1.0/24 connected directly to Switch A, inject network 8.1.1.0/24 to the BGP routing table of Switch A.
Configuration procedure
1. Configure IP addresses for interfaces. (Details not shown.)
2. Configure IBGP:
# Configure Switch B.
<SwitchB> system-view
[SwitchB] bgp 65009
[SwitchB-bgp-default] router-id 2.2.2.2
[SwitchB-bgp-default] peer 3.3.3.3 as-number 65009
[SwitchB-bgp-default] peer 3.3.3.3 connect-interface loopback 0
[SwitchB-bgp-default] address-family ipv4 unicast
[SwitchB-bgp-default-ipv4] peer 3.3.3.3 enable
[SwitchB-bgp-default-ipv4] quit
[SwitchB-bgp-default] quit
[SwitchB] ospf 1
[SwitchB-ospf-1] area 0
[SwitchB-ospf-1-area-0.0.0.0] network 2.2.2.2 0.0.0.0
[SwitchB-ospf-1-area-0.0.0.0] network 9.1.1.0 0.0.0.255
[SwitchB-ospf-1-area-0.0.0.0] quit
[SwitchB-ospf-1] quit
# Configure Switch C.
<SwitchC> system-view
[SwitchC] bgp 65009
[SwitchC-bgp-default] router-id 3.3.3.3
[SwitchC-bgp-default] peer 2.2.2.2 as-number 65009
[SwitchC-bgp-default] peer 2.2.2.2 connect-interface loopback 0
[SwitchC-bgp-default] address-family ipv4 unicast
[SwitchC-bgp-default-ipv4] peer 2.2.2.2 enable
[SwitchC-bgp-default-ipv4] quit
[SwitchC-bgp-default] quit
[SwitchC] ospf 1
[SwitchC-ospf-1] area 0
[SwitchC-ospf-1-area-0.0.0.0] network 3.3.3.3 0.0.0.0
[SwitchC-ospf-1-area-0.0.0.0] network 9.1.1.0 0.0.0.255
[SwitchC-ospf-1-area-0.0.0.0] quit
[SwitchC-ospf-1] quit
[SwitchC] display bgp peer ipv4
BGP local router ID : 3.3.3.3
Local AS number : 65009
Total number of peers : 1 Peers in established state : 1
* - Dynamically created peer
Peer AS MsgRcvd MsgSent OutQ PrefRcv Up/Down State
2.2.2.2 65009 2 2 0 0 00:00:13 Established
The output shows that Switch C has established an IBGP peer relationship with Switch B.
3. Configure EBGP:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] bgp 65008
[SwitchA-bgp-default] router-id 1.1.1.1
[SwitchA-bgp-default] peer 3.1.1.1 as-number 65009
[SwitchA-bgp-default] address-family ipv4 unicast
[SwitchA-bgp-default-ipv4] peer 3.1.1.1 enable
[SwitchA-bgp-default-ipv4] network 8.1.1.0 24
[SwitchA-bgp-default-ipv4] quit
[SwitchA-bgp-default] quit
# Configure Switch B.
[SwitchB] bgp 65009
[SwitchB-bgp-default] peer 3.1.1.2 as-number 65008
[SwitchB-bgp-default] address-family ipv4 unicast
[SwitchB-bgp-default-ipv4] peer 3.1.1.2 enable
[SwitchB-bgp-default-ipv4] quit
[SwitchB-bgp-default] quit
# Display BGP peer information on Switch B.
[SwitchB] display bgp peer ipv4
BGP local router ID : 2.2.2.2
Local AS number : 65009
Total number of peers : 2 Peers in established state : 2
* - Dynamically created peer
Peer AS MsgRcvd MsgSent OutQ PrefRcv Up/Down State
3.3.3.3 65009 4 4 0 0 00:02:49 Established
3.1.1.2 65008 2 2 0 0 00:00:05 Established
The output shows that Switch B has established an IBGP peer relationship with Switch C and an EBGP peer relationship with Switch A.
# Display the BGP routing table on Switch A.
[SwitchA] display bgp routing-table ipv4
Total number of routes: 1
BGP local router ID is 1.1.1.1
Status codes: * - valid, > - best, d - dampened, h - history,
s - suppressed, S - stale, i - internal, e - external
Origin: i - IGP, e - EGP, ? - incomplete
Network NextHop MED LocPrf PrefVal Path/Ogn
* > 8.1.1.0/24 8.1.1.1 0 32768 i
# Display the BGP routing table on Switch B.
[SwitchB] display bgp routing-table ipv4
Total number of routes: 1
BGP local router ID is 2.2.2.2
Status codes: * - valid, > - best, d - dampened, h - history,
s - suppressed, S - stale, i - internal, e - external
Origin: i - IGP, e - EGP, ? - incomplete
Network NextHop MED LocPrf PrefVal Path/Ogn
* >e 8.1.1.0/24 3.1.1.2 0 0 65008i
# Display the BGP routing table on Switch C.
[SwitchC] display bgp routing-table ipv4
Total number of routes: 1
BGP local router ID is 3.3.3.3
Status codes: * - valid, > - best, d - dampened, h - history,
s - suppressed, S - stale, i - internal, e - external
Origin: i - IGP, e - EGP, ? - incomplete
Network NextHop MED LocPrf PrefVal Path/Ogn
i 8.1.1.0/24 3.1.1.2 0 100 0 65008i
The outputs show that Switch A has learned no route to AS 65009, and Switch C has learned network 8.1.1.0, but the next hop 3.1.1.2 is unreachable. As a result, the route is invalid.
4. Redistribute direct routes:
Configure BGP to redistribute direct routes on Switch B, so that Switch A can obtain the route to 9.1.1.0/24, and Switch C can obtain the route to 3.1.1.0/24.
# Configure Switch B.
[SwitchB] bgp 65009
[SwitchB-bgp-default] address-family ipv4 unicast
[SwitchB-bgp-default-ipv4] import-route direct
[SwitchB-bgp-default-ipv4] quit
[SwitchB-bgp-default] quit
# Display the BGP routing table on Switch A.
[SwitchA] display bgp routing-table ipv4
Total number of routes: 4
BGP local router ID is 1.1.1.1
Status codes: * - valid, > - best, d - dampened, h - history,
s - suppressed, S - stale, i - internal, e - external
Origin: i - IGP, e - EGP, ? - incomplete
Network NextHop MED LocPrf PrefVal Path/Ogn
* >e 2.2.2.2/32 3.1.1.1 0 0 65009?
* >e 3.1.1.0/24 3.1.1.1 0 0 65009?
* > 8.1.1.0/24 8.1.1.1 0 32768 i
* >e 9.1.1.0/24 3.1.1.1 0 0 65009?
Two routes, 2.2.2.2/32 and 9.1.1.0/24, have been added in Switch A's routing table.
# Display the BGP routing table on Switch C.
[SwitchC] display bgp routing-table ipv4
Total number of routes: 4
BGP local router ID is 3.3.3.3
Status codes: * - valid, > - best, d - dampened, h - history,
s - suppressed, S - stale, i - internal, e - external
Origin: i - IGP, e - EGP, ? - incomplete
Network NextHop MED LocPrf PrefVal Path/Ogn
* >i 2.2.2.2/32 2.2.2.2 0 100 0 ?
* >i 3.1.1.0/24 2.2.2.2 0 100 0 ?
* >i 8.1.1.0/24 3.1.1.2 0 100 0 65008i
* >i 9.1.1.0/24 2.2.2.2 0 100 0 ?
The output shows that the route 8.1.1.0 becomes valid with the next hop as Switch A.
Verifying the configuration
# Verify that Switch C can ping 8.1.1.1.
[SwitchC] ping 8.1.1.1
Ping 8.1.1.1 (8.1.1.1): 56 data bytes, press CTRL_C to break
56 bytes from 8.1.1.1: icmp_seq=0 ttl=254 time=10.000 ms
56 bytes from 8.1.1.1: icmp_seq=1 ttl=254 time=4.000 ms
56 bytes from 8.1.1.1: icmp_seq=2 ttl=254 time=4.000 ms
56 bytes from 8.1.1.1: icmp_seq=3 ttl=254 time=3.000 ms
56 bytes from 8.1.1.1: icmp_seq=4 ttl=254 time=3.000 ms
--- Ping statistics for 8.1.1.1 ---
5 packet(s) transmitted, 5 packet(s) received, 0.0% packet loss
round-trip min/avg/max/std-dev = 3.000/4.800/10.000/2.638 ms
BGP and IGP route redistribution configuration example
Network requirements
As shown in Figure 66, all devices of company A belong to AS 65008, and all devices of company B belong to AS 65009.
Configure BGP and IGP route redistribution to allow Switch A to access network 9.1.2.0/24 in AS 65009, and Switch C to access network 8.1.1.0/24 in AS 65008.
Configuration considerations
Configure BGP to redistribute routes from OSPF on Switch B, so Switch A can obtain the route to 9.1.2.0/24. Configure OSPF to redistribute routes from BGP on Switch B, so Switch C can obtain the route to 8.1.1.0/24.
Configuration procedure
1. Configure IP addresses for interfaces. (Details not shown.)
2. Configure OSPF:
Enable OSPF in AS 65009, so Switch B can obtain the route to 9.1.2.0/24.
# Configure Switch B.
<SwitchB> system-view
[SwitchB] ospf 1
[SwitchB-ospf-1] area 0
[SwitchB-ospf-1-area-0.0.0.0] network 2.2.2.2 0.0.0.0
[SwitchB-ospf-1-area-0.0.0.0] network 9.1.1.0 0.0.0.255
[SwitchB-ospf-1-area-0.0.0.0] quit
[SwitchB-ospf-1] quit
# Configure Switch C.
<SwitchC> system-view
[SwitchC] ospf 1
[SwitchC-ospf-1] import-route direct
[SwitchC-ospf-1] area 0
[SwitchC-ospf-1-area-0.0.0.0] network 9.1.1.0 0.0.0.255
[SwitchC-ospf-1-area-0.0.0.0] quit
[SwitchC-ospf-1] quit
3. Configure the EBGP connection:
Configure the EBGP connection and inject network 8.1.1.0/24 to the BGP routing table of Switch A, so that Switch B can obtain the route to 8.1.1.0/24.
# Configure Switch A.
<SwitchA> system-view
[SwitchA] bgp 65008
[SwitchA-bgp-default] router-id 1.1.1.1
[SwitchA-bgp-default] peer 3.1.1.1 as-number 65009
[SwitchA-bgp-default] address-family ipv4 unicast
[SwitchA-bgp-default-ipv4] peer 3.1.1.1 enable
[SwitchA-bgp-default-ipv4] network 8.1.1.0 24
[SwitchA-bgp-default-ipv4] quit
[SwitchA-bgp-default] quit
# Configure Switch B.
[SwitchB] bgp 65009
[SwitchB-bgp-default] router-id 2.2.2.2
[SwitchB-bgp-default] peer 3.1.1.2 as-number 65008
[SwitchB-bgp-default] address-family ipv4 unicast
[SwitchB-bgp-default-ipv4] peer 3.1.1.2 enable
4. Configure BGP and IGP route redistribution:
# Configure route redistribution between BGP and OSPF on Switch B.
[SwitchB-bgp-default-ipv4] import-route ospf 1
[SwitchB-bgp-default-ipv4] quit
[SwitchB-bgp-default] quit
[SwitchB] ospf 1
[SwitchB-ospf-1] import-route bgp
[SwitchB-ospf-1] quit
# Display the BGP routing table on Switch A.
[SwitchA] display bgp routing-table ipv4
Total number of routes: 3
BGP local router ID is 1.1.1.1
Status codes: * - valid, > - best, d - dampened, h - history,
s - suppressed, S - stale, i - internal, e - external
Origin: i - IGP, e - EGP, ? - incomplete
Network NextHop MED LocPrf PrefVal Path/Ogn
* >e 3.3.3.3/32 3.1.1.1 1 0 65009?
* > 8.1.1.0/24 8.1.1.1 0 32768 i
* >e 9.1.2.0/24 3.1.1.1 1 0 65009?
# Display the OSPF routing table on Switch C.
[SwitchC] display ospf routing
OSPF Process 1 with Router ID 3.3.3.3
Routing Tables
Routing for Network
Destination Cost Type NextHop AdvRouter Area
9.1.1.0/24 1 Transit 9.1.1.2 3.3.3.3 0.0.0.0
2.2.2.2/32 1 Stub 9.1.1.1 2.2.2.2 0.0.0.0
Routing for ASEs
Destination Cost Type Tag NextHop AdvRouter
8.1.1.0/24 1 Type2 1 9.1.1.1 2.2.2.2
Total Nets: 3
Intra Area: 2 Inter Area: 0 ASE: 1 NSSA: 0
Verifying the configuration
# Use ping for verification.
[SwitchA] ping -a 8.1.1.1 9.1.2.1
Ping 9.1.2.1 (9.1.2.1) from 8.1.1.1: 56 data bytes, press CTRL_C to break
56 bytes from 9.1.2.1: icmp_seq=0 ttl=254 time=10.000 ms
56 bytes from 9.1.2.1: icmp_seq=1 ttl=254 time=12.000 ms
56 bytes from 9.1.2.1: icmp_seq=2 ttl=254 time=2.000 ms
56 bytes from 9.1.2.1: icmp_seq=3 ttl=254 time=7.000 ms
56 bytes from 9.1.2.1: icmp_seq=4 ttl=254 time=9.000 ms
--- Ping statistics for 9.1.2.1 ---
5 packet(s) transmitted, 5 packet(s) received, 0.0% packet loss
round-trip min/avg/max/std-dev = 2.000/8.000/12.000/3.406 ms
[SwitchC] ping -a 9.1.2.1 8.1.1.1
Ping 8.1.1.1 (8.1.1.1) from 9.1.2.1: 56 data bytes, press CTRL_C to break
56 bytes from 8.1.1.1: icmp_seq=0 ttl=254 time=9.000 ms
56 bytes from 8.1.1.1: icmp_seq=1 ttl=254 time=4.000 ms
56 bytes from 8.1.1.1: icmp_seq=2 ttl=254 time=3.000 ms
56 bytes from 8.1.1.1: icmp_seq=3 ttl=254 time=3.000 ms
56 bytes from 8.1.1.1: icmp_seq=4 ttl=254 time=3.000 ms
--- Ping statistics for 8.1.1.1 ---
5 packet(s) transmitted, 5 packet(s) received, 0.0% packet loss
round-trip min/avg/max/std-dev = 3.000/4.400/9.000/2.332 ms
BGP route summarization configuration example
Network requirements
As shown in Figure 67, run EBGP between Switch C and Switch D, so the internal network and external network can communicate with each other.
· In AS 65106, perform the following configurations so the devices in the internal network can communicate:
? Configure static routing between Switch A and Switch B.
? Configure OSPF between Switch B and Switch C.
? Configure OSPF to redistribute static routes.
· Configure route summarization on Switch C so BGP advertises a summary route instead of advertising routes to the 192.168.64.0/24, 192.168.74.0/24, and 192.168.99.0/24 networks to Switch D.
Configuration procedure
1. Configure IP addresses for interfaces. (Details not shown.)
2. Configure static routing between Switch A and Switch B:
# Configure a default route with the next hop 192.168.212.1 on Switch A.
<SwitchA> system-view
[SwitchA] ip route-static 0.0.0.0 0 192.168.212.1
# Configure static routes to 192.168.64.0/24, 192.168.74.0/24, and 192.168.99.0/24 with the same next hop 192.168.212.161 on Switch B.
<SwitchB> system-view
[SwitchB] ip route-static 192.168.64.0 24 192.168.212.161
[SwitchB] ip route-static 192.168.74.0 24 192.168.212.161
[SwitchB] ip route-static 192.168.99.0 24 192.168.212.161
3. Configure OSPF between Switch B and Switch C and configure OSPF on Switch B to redistribute static routes:
# Configure OSPF to advertise the local network and enable OSPF to redistribute static routes on Switch B.
[SwitchB] ospf
[SwitchB-ospf-1] area 0
[SwitchB-ospf-1-area-0.0.0.0] network 172.17.100.0 0.0.0.255
[SwitchB-ospf-1-area-0.0.0.0] quit
[SwitchB-ospf-1] import-route static
[SwitchB-ospf-1] quit
# Configure OSPF to advertise the local networks on Switch C.
[SwitchC] ospf
[SwitchC-ospf-1] area 0
[SwitchC-ospf-1-area-0.0.0.0] network 172.17.100.0 0.0.0.255
[SwitchC-ospf-1-area-0.0.0.0] network 10.220.2.0 0.0.0.255
[SwitchC-ospf-1-area-0.0.0.0] quit
[SwitchC-ospf-1] quit
# Display the IP routing table on Switch C.
[SwitchC] display ip routing-table protocol ospf
Summary count : 5
OSPF Routing table Status : <Active>
Summary count : 3
Destination/Mask Proto Pre Cost NextHop Interface
192.168.64.0/24 OSPF 150 1 172.17.100.1 Vlan100
192.168.74.0/24 OSPF 150 1 172.17.100.1 Vlan100
192.168.99.0/24 OSPF 150 1 172.17.100.1 Vlan100
OSPF Routing table Status : <Inactive>
Summary count : 2
Destination/Mask Proto Pre Cost NextHop Interface
10.220.2.0/24 OSPF 10 1 10.220.2.16 Vlan200
172.17.100.0/24 OSPF 10 1 172.17.100.2 Vlan100
The output shows that Switch C has learned routes to 192.168.64.0/24, 192.168.99.0/24, and 192.168.64.0/18 through OSPF.
4. Configure BGP between Switch C and Switch D and configure BGP on Switch C to redistribute OSPF routes:
# On Switch C, enable BGP, specify Switch D as an EBGP peer, and configure BGP to redistribute OSPF routes.
[SwitchC] bgp 65106
[SwitchC-bgp-default] router-id 3.3.3.3
[SwitchC-bgp-default] peer 10.220.2.217 as-number 64631
[SwitchC-bgp-default] address-family ipv4 unicast
[SwitchC-bgp-default-ipv4] peer 10.220.2.217 enable
[SwitchC-bgp-default-ipv4] import-route ospf
# Enable BGP, and configure Switch C as an EBGP peer on Switch D.
[SwitchD] bgp 64631
[SwitchD-bgp-default] router-id 4.4.4.4
[SwitchD-bgp-default] peer 10.220.2.16 as-number 65106
[SwitchD-bgp-default] address-family ipv4 unicast
[SwitchD-bgp-default-ipv4] peer 10.220.2.16 enable
[SwitchD-bgp-default-ipv4] quit
[SwitchD-bgp-default] quit
# Display the IP routing table on Switch D.
[SwitchD] display ip routing-table protocol bgp
Summary count : 3
BGP Routing table Status : <Active>
Summary count : 3
Destination/Mask Proto Pre Cost NextHop Interface
192.168.64.0/24 BGP 255 1 10.220.2.16 Vlan200
192.168.74.0/24 BGP 255 1 10.220.2.16 Vlan200
192.168.99.0/24 BGP 255 1 10.220.2.16 Vlan200
BGP Routing table Status : <Inactive>
Summary count : 0
The output shows that Switch D has learned routes to 192.168.64.0/24, 192.168.74.0/24, and 192.168.99.0/24 through BGP.
# Verify that Switch D can ping hosts on networks 192.168.74.0/24, 192.168.99.0/24, and 192.168.64.0/18. (Details not shown.)
5. Configure route summarization on Switch C to summarize 192.168.64.0/24, 192.168.74.0/24, and 192.168.99.0/24 into a single route 192.168.64.0/18, and disable advertisement of specific routes.
[SwitchC-bgp-default-ipv4] aggregate 192.168.64.0 18 detail-suppressed
[SwitchC-bgp-default-ipv4] quit
[SwitchC-bgp-default] quit
Verifying the configuration
# Display IP routing table on Switch C.
[SwitchC] display ip routing-table | include 192.168
192.168.64.0/18 BGP 130 0 127.0.0.1 NULL0
192.168.64.0/24 OSPF 150 1 172.17.100.1 Vlan100
192.168.74.0/24 OSPF 150 1 172.17.100.1 Vlan100
192.168.99.0/24 OSPF 150 1 172.17.100.1 Vlan100
The output shows that Switch C has a summary route 192.168.64.0/18 with the output interface Null0.
# Display IP routing table on Switch D.
[SwitchD] display ip routing-table protocol bgp
Summary count : 1
BGP Routing table Status : <Active>
Summary count : 1
Destination/Mask Proto Pre Cost NextHop Interface
192.168.64.0/18 BGP 255 0 10.220.2.16 Vlan200
BGP Routing table Status : <Inactive>
Summary count : 0
The output shows that Switch D has only one route 192.168.64.0/18 to AS 65106.
# Verify that Switch D can ping the hosts on networks 192.168.64.0/24, 192.168.74.0/24, and 192.168.99.0/24. (Details not shown.)
BGP load balancing configuration example
Network requirements
As shown in Figure 68, run EBGP between Switch A and Switch B, and between Switch A and Switch C. Run IBGP between Switch B and Switch C. Configure load balancing over the two EBGP links on Switch A.
Configuration considerations
On Switch A:
· Establish EBGP connections with Switch B and Switch C.
· Configure BGP to advertise network 8.1.1.0/24 to Switch B and Switch C, so that Switch B and Switch C can access the internal network connected to Switch A.
On Switch B:
· Establish an EBGP connection with Switch A and an IBGP connection with Switch C.
· Configure BGP to advertise network 9.1.1.0/24 to Switch A, so that Switch A can access the intranet through Switch B.
· Configure a static route to interface loopback 0 on Switch C (or use a routing protocol like OSPF) to establish the IBGP connection.
On Switch C:
· Establish an EBGP connection with Switch A and an IBGP connection with Switch B.
· Configure BGP to advertise network 9.1.1.0/24 to Switch A, so that Switch A can access the intranet through Switch C.
· Configure a static route to interface loopback 0 on Switch B (or use another protocol like OSPF) to establish the IBGP connection.
Configure load balancing on Switch A.
Configuration procedure
1. Configure IP addresses for interfaces. (Details not shown.)
2. Configure BGP connections:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] bgp 65008
[SwitchA-bgp-default] router-id 1.1.1.1
[SwitchA-bgp-default] peer 3.1.1.1 as-number 65009
[SwitchA-bgp-default] peer 3.1.2.1 as-number 65009
[SwitchA-bgp-default] address-family ipv4 unicast
[SwitchA-bgp-default-ipv4] peer 3.1.1.1 enable
[SwitchA-bgp-default-ipv4] peer 3.1.2.1 enable
[SwitchA-bgp-default-ipv4] network 8.1.1.0 24
[SwitchA-bgp-default-ipv4] quit
[SwitchA-bgp-default] quit
# Configure Switch B.
<SwitchB> system-view
[SwitchB] bgp 65009
[SwitchB-bgp-default] router-id 2.2.2.2
[SwitchB-bgp-default] peer 3.1.1.2 as-number 65008
[SwitchB-bgp-default] peer 3.3.3.3 as-number 65009
[SwitchB-bgp-default] peer 3.3.3.3 connect-interface loopback 0
[SwitchB-bgp-default] address-family ipv4 unicast
[SwitchB-bgp-default-ipv4] peer 3.1.1.2 enable
[SwitchB-bgp-default-ipv4] peer 3.3.3.3 enable
[SwitchB-bgp-default-ipv4] network 9.1.1.0 24
[SwitchB-bgp-default-ipv4] quit
[SwitchB-bgp-default] quit
[SwitchB] ip route-static 3.3.3.3 32 9.1.1.2
# Configure Switch C.
<SwitchC> system-view
[SwitchC] bgp 65009
[SwitchC-bgp-default] router-id 3.3.3.3
[SwitchC-bgp-default] peer 3.1.2.2 as-number 65008
[SwitchC-bgp-default] peer 2.2.2.2 as-number 65009
[SwitchC-bgp-default] peer 2.2.2.2 connect-interface loopback 0
[SwitchC-bgp-default] address-family ipv4 unicast
[SwitchC-bgp-default-ipv4] peer 3.1.2.2 enable
[SwitchC-bgp-default-ipv4] peer 2.2.2.2 enable
[SwitchC-bgp-default-ipv4] network 9.1.1.0 24
[SwitchC-bgp-default-ipv4] quit
[SwitchC-bgp-default] quit
[SwitchC] ip route-static 2.2.2.2 32 9.1.1.1
# Display the BGP routing table on Switch A.
[SwitchA] display bgp routing-table ipv4
Total number of routes: 3
BGP local router ID is 1.1.1.1
Status codes: * - valid, > - best, d - dampened, h - history,
s - suppressed, S - stale, i - internal, e - external
Origin: i - IGP, e - EGP, ? - incomplete
Network NextHop MED LocPrf PrefVal Path/Ogn
* > 8.1.1.0/24 8.1.1.1 0 32768 i
* >e 9.1.1.0/24 3.1.1.1 0 0 65009i
* e 3.1.2.1 0 0 65009i
? The output shows two valid routes to destination 9.1.1.0/24. The route with next hop 3.1.1.1 is marked with a greater-than sign (>), indicating that it is the optimal route (because the ID of Switch B is smaller). The route with next hop 3.1.2.1 is marked with an asterisk (*), indicating that it is a valid route, but not the optimal route.
? By using the display ip routing-table command, you can find only one route to 9.1.1.0/24 with next hop 3.1.1.1 and output interface VLAN-interface 200.
3. Configure loading balancing:
Because Switch A has two routes to reach AS 65009, configuring load balancing over the two BGP routes on Switch A can improve link usage.
# Configure Switch A.
[SwitchA] bgp 65008
[SwitchA-bgp-default] address-family ipv4 unicast
[SwitchA-bgp-default-ipv4] balance 2
[SwitchA-bgp-default-ipv4] quit
[SwitchA-bgp-default] quit
Verifying the configuration
# Display the BGP routing table on Switch A.
[SwitchA] display bgp routing-table ipv4
Total number of routes: 3
BGP local router ID is 1.1.1.1
Status codes: * - valid, > - best, d - dampened, h - history,
s - suppressed, S - stale, i - internal, e - external
Origin: i - IGP, e - EGP, ? - incomplete
Network NextHop MED LocPrf PrefVal Path/Ogn
* > 8.1.1.0/24 8.1.1.1 0 32768 i
* >e 9.1.1.0/24 3.1.1.1 0 0 65009i
* >e 3.1.2.1 0 0 65009i
· The route 9.1.1.0/24 has two next hops, 3.1.1.1 and 3.1.2.1, both of which are marked with a greater-than sign (>), indicating that they are the optimal routes.
· By using the display ip routing-table command, you can find two routes to 9.1.1.0/24. One has next hop 3.1.1.1 and output interface VLAN-interface 200, and the other has next hop 3.1.2.1 and output interface VLAN-interface 300.
BGP community configuration example
Network requirements
As shown in Figure 69, Switch B establishes EBGP connections with Switch A and Switch C. Configure NO_EXPORT community attribute on Switch A to make routes from AS 10 not advertised by AS 20 to any other AS.
Configuration procedure
1. Configure IP addresses for interfaces. (Details not shown.)
2. Configure EBGP connections:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] bgp 10
[SwitchA-bgp-default] router-id 1.1.1.1
[SwitchA-bgp-default] peer 200.1.2.2 as-number 20
[SwitchA-bgp-default] address-family ipv4 unicast
[SwitchA-bgp-default-ipv4] peer 200.1.2.2 enable
[SwitchA-bgp-default-ipv4] network 9.1.1.0 255.255.255.0
[SwitchA-bgp-default] quit
# Configure Switch B.
<SwitchB> system-view
[SwitchB] bgp 20
[SwitchB-bgp-default] router-id 2.2.2.2
[SwitchB-bgp-default] peer 200.1.2.1 as-number 10
[SwitchB-bgp-default] peer 200.1.3.2 as-number 30
[SwitchB-bgp-default] address-family ipv4 unicast
[SwitchB-bgp-default-ipv4] peer 200.1.2.1 enable
[SwitchB-bgp-default-ipv4] peer 200.1.3.2 enable
[SwitchB-bgp-default-ipv4] quit
[SwitchB-bgp-default] quit
# Configure Switch C.
<SwitchC> system-view
[SwitchC] bgp 30
[SwitchC-bgp-default] router-id 3.3.3.3
[SwitchC-bgp-default] peer 200.1.3.1 as-number 20
[SwitchC-bgp-default] address-family ipv4 unicast
[SwitchC-bgp-default-ipv4] peer 200.1.3.1 enable
[SwitchC-bgp-default-ipv4] quit
[SwitchC-bgp-default] quit
# Display the BGP routing table on Switch B.
[SwitchB] display bgp routing-table ipv4 9.1.1.0
BGP local router ID: 2.2.2.2
Local AS number: 20
Paths: 1 available, 1 best
BGP routing table information of 9.1.1.0/24:
From : 200.1.2.1 (1.1.1.1)
Rely nexthop : 200.1.2.1
Original nexthop: 200.1.2.1
OutLabel : NULL
AS-path : 10
Origin : igp
Attribute value : pref-val 0
State : valid, external, best
IP precedence : N/A
QoS local ID : N/A
Traffic index : N/A
# Display advertisement information of network 9.1.1.0 on Switch B.
[SwitchB] display bgp routing-table ipv4 9.1.1.0 advertise-info
BGP local router ID: 2.2.2.2
Local AS number: 20
Paths: 1 best
BGP routing table information of 9.1.1.0/24:
Advertised to peers (1 in total):
200.1.3.2
The output shows that Switch B can advertise the route with the destination 9.1.1.0/24 to other ASs through BGP.
# Display the BGP routing table on Switch C.
[SwitchC] display bgp routing-table ipv4
Total number of routes: 1
BGP local router ID is 3.3.3.3
Status codes: * - valid, > - best, d - dampened, h - history,
s - suppressed, S - stale, i - internal, e - external
Origin: i - IGP, e - EGP, ? - incomplete
Network NextHop MED LocPrf PrefVal Path/Ogn
* >e 9.1.1.0/24 200.1.3.1 0 20 10i
The output shows that Switch C has learned route 9.1.1.0/24 from Switch B.
3. Configure BGP community:
# Configure a routing policy.
[SwitchA] route-policy comm_policy permit node 0
[SwitchA-route-policy-comm_policy-0] apply community no-export
[SwitchA-route-policy-comm_policy-0] quit
# Apply the routing policy.
[SwitchA] bgp 10
[SwitchA-bgp-default] address-family ipv4 unicast
[SwitchA-bgp-default-ipv4] peer 200.1.2.2 route-policy comm_policy export
[SwitchA-bgp-default-ipv4] peer 200.1.2.2 advertise-community
Verifying the configuration
# Display the routing table on Switch B.
[SwitchB] display bgp routing-table ipv4 9.1.1.0
BGP local router ID: 2.2.2.2
Local AS number: 20
Paths: 1 available, 1 best
BGP routing table information of 9.1.1.0/24:
From : 200.1.2.1 (1.1.1.1)
Rely nexthop : 200.1.2.1
Original nexthop: 200.1.2.1
OutLabel : NULL
Community : No-Export
AS-path : 10
Origin : igp
Attribute value : pref-val 0
State : valid, external, best
IP precedence : N/A
QoS local ID : N/A
Traffic index : N/A
# Display advertisement information for the route 9.1.1.0 on Switch B.
[SwitchB] display bgp routing-table ipv4 9.1.1.0 advertise-info
BGP local router ID: 2.2.2.2
Local AS number: 20
Paths: 1 best
BGP routing table information of 9.1.1.0/24:
Not advertised to any peers yet
# Display the BGP routing table on Switch C.
[SwitchC] display bgp routing-table ipv4
Total number of routes: 0
The output shows that BGP has not learned any route.
BGP route reflector configuration example
Network requirements
As shown in Figure 70, all switches run BGP. Run EBGP between Switch A and Switch B, and run IBGP between Switch C and Switch B, and between Switch C and Switch D.
Configure Switch C as a route reflector with clients Switch B and Switch D to allow Switch D to learn route 20.0.0.0/8 from Switch C.
Configuration procedure
1. Configure IP addresses for interfaces and configure OSPF in AS 200. (Details not shown.)
2. Configure BGP connections:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] bgp 100
[SwitchA-bgp-default] router-id 1.1.1.1
[SwitchA-bgp-default] peer 192.1.1.2 as-number 200
[SwitchA-bgp-default] address-family ipv4 unicast
[SwitchA-bgp-default-ipv4] peer 192.1.1.2 enable
# Inject network 20.0.0.0/8 to the BGP routing table.
[SwitchA-bgp-default-ipv4] network 20.0.0.0
[SwitchA-bgp-default-ipv4] quit
[SwitchA-bgp-default] quit
# Configure Switch B.
<SwitchB> system-view
[SwitchB] bgp 200
[SwitchB-bgp-default] router-id 2.2.2.2
[SwitchB-bgp-default] peer 192.1.1.1 as-number 100
[SwitchB-bgp-default] peer 193.1.1.1 as-number 200
[SwitchB-bgp-default] address-family ipv4 unicast
[SwitchB-bgp-default-ipv4] peer 192.1.1.1 enable
[SwitchB-bgp-default-ipv4] peer 193.1.1.1 enable
[SwitchB-bgp-default-ipv4] peer 193.1.1.1 next-hop-local
[SwitchB-bgp-default-ipv4] quit
[SwitchB-bgp-default] quit
# Configure Switch C.
<SwitchC> system-view
[SwitchC] bgp 200
[SwitchC-bgp-default] router-id 3.3.3.3
[SwitchC-bgp-default] peer 193.1.1.2 as-number 200
[SwitchC-bgp-default] peer 194.1.1.2 as-number 200
[SwitchC-bgp-default] address-family ipv4 unicast
[SwitchC-bgp-default-ipv4] peer 193.1.1.2 enable
[SwitchC-bgp-default-ipv4] peer 194.1.1.2 enable
[SwitchC-bgp-default-ipv4] quit
[SwitchC-bgp-default] quit
# Configure Switch D.
<SwitchD> system-view
[SwitchD] bgp 200
[SwitchD-bgp-default] router-id 4.4.4.4
[SwitchD-bgp-default] peer 194.1.1.1 as-number 200
[SwitchD-bgp-default] address-family ipv4 unicast
[SwitchD-bgp-default-ipv4] peer 194.1.1.1 enable
[SwitchD-bgp-default-ipv4] quit
[SwitchD-bgp-default] quit
3. Configure Switch C as the route reflector.
[SwitchC] bgp 200
[SwitchC-bgp-default] address-family ipv4 unicast
[SwitchC-bgp-default-ipv4] peer 193.1.1.2 reflect-client
[SwitchC-bgp-default-ipv4] peer 194.1.1.2 reflect-client
[SwitchC-bgp-default-ipv4] quit
[SwitchC-bgp-default] quit
Verifying the configuration
# Display the BGP routing table on Switch B.
[SwitchB] display bgp routing-table ipv4
Total number of routes: 1
BGP local router ID is 2.2.2.2
Status codes: * - valid, > - best, d - dampened, h - history,
s - suppressed, S - stale, i - internal, e - external
Origin: i - IGP, e - EGP, ? - incomplete
Network NextHop MED LocPrf PrefVal Path/Ogn
* >e 20.0.0.0 192.1.1.1 0 0 100i
# Display the BGP routing table on Switch D.
[SwitchD] display bgp routing-table ipv4
Total number of routes: 1
BGP local router ID is 4.4.4.4
Status codes: * - valid, > - best, d - dampened, h - history,
s - suppressed, S - stale, i - internal, e - external
Origin: i - IGP, e - EGP, ? - incomplete
Network NextHop MED LocPrf PrefVal Path/Ogn
* >i 20.0.0.0 193.1.1.2 0 100 0 100i
The output shows that Switch D has learned route 20.0.0.0/8 from Switch C.
BGP confederation configuration example
Network requirements
As shown in Figure 71, split AS 200 into three sub-ASs (AS 65001, AS 65002, and AS 65003) to reduce IBGP connections. Switches in AS 65001 are fully meshed.
Table 17 Interface and IP address assignment
Device |
Interface |
IP address |
Device |
Interface |
IP address |
Switch A |
Vlan-int100 |
200.1.1.1/24 |
Switch D |
Vlan-int200 |
10.1.5.1/24 |
|
Vlan-int200 |
10.1.1.1/24 |
|
Vlan-int400 |
10.1.3.2/24 |
|
Vlan-int300 |
10.1.2.1/24 |
Switch E |
Vlan-int200 |
10.1.5.2/24 |
|
Vlan-int400 |
10.1.3.1/24 |
|
Vlan-int500 |
10.1.4.2/24 |
|
Vlan-int500 |
10.1.4.1/24 |
Switch F |
Vlan-int100 |
200.1.1.2/24 |
Switch B |
Vlan-int200 |
10.1.1.2/24 |
|
Vlan-int600 |
9.1.1.1/24 |
Switch C |
Vlan-int300 |
10.1.2.2/24 |
|
|
|
Configuration procedure
1. Configure IP addresses for interfaces. (Details not shown.)
2. Configure BGP confederation:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] bgp 65001
[SwitchA-bgp-default] router-id 1.1.1.1
[SwitchA-bgp-default] confederation id 200
[SwitchA-bgp-default] confederation peer-as 65002 65003
[SwitchA-bgp-default] peer 10.1.1.2 as-number 65002
[SwitchA-bgp-default] peer 10.1.2.2 as-number 65003
[SwitchA-bgp-default] address-family ipv4 unicast
[SwitchA-bgp-default-ipv4] peer 10.1.1.2 enable
[SwitchA-bgp-default-ipv4] peer 10.1.2.2 enable
[SwitchA-bgp-default-ipv4] peer 10.1.1.2 next-hop-local
[SwitchA-bgp-default-ipv4] peer 10.1.2.2 next-hop-local
[SwitchA-bgp-default-ipv4] quit
[SwitchA-bgp-default] quit
# Configure Switch B.
<SwitchB> system-view
[SwitchB] bgp 65002
[SwitchB-bgp-default] router-id 2.2.2.2
[SwitchB-bgp-default] confederation id 200
[SwitchB-bgp-default] confederation peer-as 65001 65003
[SwitchB-bgp-default] peer 10.1.1.1 as-number 65001
[SwitchB-bgp-default] address-family ipv4 unicast
[SwitchB-bgp-default-ipv4] peer 10.1.1.1 enable
[SwitchB-bgp-default-ipv4] quit
[SwitchB-bgp-default] quit
# Configure Switch C.
<SwitchC> system-view
[SwitchC] bgp 65003
[SwitchC-bgp-default] router-id 3.3.3.3
[SwitchC-bgp-default] confederation id 200
[SwitchC-bgp-default] confederation peer-as 65001 65002
[SwitchC-bgp-default] peer 10.1.2.1 as-number 65001
[SwitchC-bgp-default] address-family ipv4 unicast
[SwitchC-bgp-default-ipv4] peer 10.1.2.1 enable
[SwitchC-bgp-default-ipv4] quit
[SwitchC-bgp-default] quit
3. Configure IBGP connections in AS 65001:
# Configure Switch A.
[SwitchA] bgp 65001
[SwitchA-bgp-default] peer 10.1.3.2 as-number 65001
[SwitchA-bgp-default] peer 10.1.4.2 as-number 65001
[SwitchA-bgp-default] address-family ipv4 unicast
[SwitchA-bgp-default-ipv4] peer 10.1.3.2 enable
[SwitchA-bgp-default-ipv4] peer 10.1.4.2 enable
[SwitchA-bgp-default-ipv4] peer 10.1.3.2 next-hop-local
[SwitchA-bgp-default-ipv4] peer 10.1.4.2 next-hop-local
[SwitchA-bgp-default-ipv4] quit
[SwitchA-bgp-default] quit
# Configure Switch D.
<SwitchD> system-view
[SwitchD] bgp 65001
[SwitchD-bgp-default] router-id 4.4.4.4
[SwitchD-bgp-default] confederation id 200
[SwitchD-bgp-default] peer 10.1.3.1 as-number 65001
[SwitchD-bgp-default] peer 10.1.5.2 as-number 65001
[SwitchD-bgp-default] address-family ipv4 unicast
[SwitchD-bgp-default-ipv4] peer 10.1.3.1 enable
[SwitchD-bgp-default-ipv4] peer 10.1.5.2 enable
[SwitchD-bgp-default-ipv4] quit
[SwitchD-bgp-default] quit
# Configure Switch E.
<SwitchE> system-view
[SwitchE] bgp 65001
[SwitchE-bgp-default] router-id 5.5.5.5
[SwitchE-bgp-default] confederation id 200
[SwitchE-bgp-default] peer 10.1.4.1 as-number 65001
[SwitchE-bgp-default] peer 10.1.5.1 as-number 65001
[SwitchE-bgp-default] address-family ipv4 unicast
[SwitchE-bgp-default-ipv4] peer 10.1.4.1 enable
[SwitchE-bgp-default-ipv4] peer 10.1.5.1 enable
[SwitchE-bgp-default-ipv4] quit
[SwitchE-bgp-default] quit
4. Configure the EBGP connection between AS 100 and AS 200:
# Configure Switch A.
[SwitchA] bgp 65001
[SwitchA-bgp-default] peer 200.1.1.2 as-number 100
[SwitchA-bgp-default] address-family ipv4 unicast
[SwitchA-bgp-default-ipv4] peer 200.1.1.2 enable
[SwitchA-bgp-default-ipv4] quit
[SwitchA-bgp-default] quit
# Configure Switch F.
<SwitchF> system-view
[SwitchF] bgp 100
[SwitchF-bgp-default] router-id 6.6.6.6
[SwitchF-bgp-default] peer 200.1.1.1 as-number 200
[SwitchF-bgp-default] address-family ipv4 unicast
[SwitchF-bgp-default-ipv4] peer 200.1.1.1 enable
[SwitchF-bgp-default-ipv4] network 9.1.1.0 255.255.255.0
[SwitchF-bgp-default-ipv4] quit
[SwitchF-bgp-default] quit
Verifying the configuration
# Display the routing table on Switch B.
[SwitchB] display bgp routing-table ipv4
Total number of routes: 1
BGP local router ID is 2.2.2.2
Status codes: * - valid, > - best, d - dampened, h - history,
s - suppressed, S - stale, i - internal, e - external
Origin: i - IGP, e - EGP, ? - incomplete
Network NextHop MED LocPrf PrefVal Path/Ogn
* >i 9.1.1.0/24 10.1.1.1 0 100 0 (65001)
100i
[SwitchB] display bgp routing-table ipv4 9.1.1.0
BGP local router ID: 2.2.2.2
Local AS number: 65002
Paths: 1 available, 1 best
BGP routing table information of 9.1.1.0/24:
From : 10.1.1.1 (1.1.1.1)
Rely nexthop : 10.1.1.1
Original nexthop: 10.1.1.1
OutLabel : NULL
AS-path : (65001) 100
Origin : igp
Attribute value : MED 0, localpref 100, pref-val 0, pre 255
State : valid, external-confed, best
IP precedence : N/A
QoS local ID : N/A
Traffic index : N/A
# Display the BGP routing table on Switch D.
[SwitchD] display bgp routing-table ipv4
Total number of routes: 1
BGP local router ID is 4.4.4.4
Status codes: * - valid, > - best, d - dampened, h - history,
s - suppressed, S - stale, i - internal, e - external
Origin: i - IGP, e - EGP, ? - incomplete
Network NextHop MED LocPrf PrefVal Path/Ogn
* >i 9.1.1.0/24 10.1.3.1 0 100 0 100i
[SwitchD] display bgp routing-table ipv4 9.1.1.0
BGP local router ID: 4.4.4.4
Local AS number: 65001
Paths: 1 available, 1 best
BGP routing table information of 9.1.1.0/24:
From : 10.1.3.1 (1.1.1.1)
Rely nexthop : 10.1.3.1
Original nexthop: 10.1.3.1
OutLabel : NULL
AS-path : 100
Origin : igp
Attribute value : MED 0, localpref 100, pref-val 0, pre 255
State : valid, internal-confed, best
IP precedence : N/A
QoS local ID : N/A
Traffic index : N/A
The output shows the following:
· Switch F can send route information to Switch B and Switch C through the confederation by establishing only an EBGP connection with Switch A.
· Switch B and Switch D are in the same confederation, but belong to different sub-ASs. They obtain external route information from Switch A, and generate identical BGP route entries although they have no direct connection in between.
BGP path selection configuration example
Network requirements
As shown in Figure 72, all switches run BGP.
· EBGP runs between Switch A and Switch B, and between Switch A and Switch C.
· IBGP runs between Switch B and Switch D, and between Switch D and Switch C. OSPF is the IGP protocol in AS 200.
Configure routing policies, making Switch D use the route 1.0.0.0/8 from Switch C as the optimal.
Table 18 Interface and IP address assignment
Device |
Interface |
IP address |
Device |
Interface |
IP address |
Switch A |
Vlan-int101 |
1.0.0.1/8 |
Switch D |
Vlan-int400 |
195.1.1.1/24 |
|
Vlan-int100 |
192.1.1.1/24 |
|
Vlan-int300 |
194.1.1.1/24 |
|
Vlan-int200 |
193.1.1.1/24 |
Switch C |
Vlan-int400 |
195.1.1.2/24 |
Switch B |
Vlan-int100 |
192.1.1.2/24 |
|
Vlan-int200 |
193.1.1.2/24 |
|
Vlan-int300 |
194.1.1.2/24 |
|
|
|
Configuration procedure
1. Configure IP addresses for interfaces. (Details not shown.)
2. Configure OSPF on Switch B, Switch C, and Switch D:
# Configure Switch B.
<SwitchB> system-view
[SwitchB] ospf
[SwitchB-ospf] area 0
[SwitchB-ospf-1-area-0.0.0.0] network 192.1.1.0 0.0.0.255
[SwitchB-ospf-1-area-0.0.0.0] network 194.1.1.0 0.0.0.255
[SwitchB-ospf-1-area-0.0.0.0] quit
[SwitchB-ospf-1] quit
# Configure Switch C.
<SwitchC> system-view
[SwitchC] ospf
[SwitchC-ospf] area 0
[SwitchC-ospf-1-area-0.0.0.0] network 193.1.1.0 0.0.0.255
[SwitchC-ospf-1-area-0.0.0.0] network 195.1.1.0 0.0.0.255
[SwitchC-ospf-1-area-0.0.0.0] quit
[SwitchC-ospf-1] quit
# Configure Switch D.
<SwitchD> system-view
[SwitchD] ospf
[SwitchD-ospf] area 0
[SwitchD-ospf-1-area-0.0.0.0] network 194.1.1.0 0.0.0.255
[SwitchD-ospf-1-area-0.0.0.0] network 195.1.1.0 0.0.0.255
[SwitchD-ospf-1-area-0.0.0.0] quit
[SwitchD-ospf-1] quit
3. Configure BGP connections:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] bgp 100
[SwitchA-bgp-default] peer 192.1.1.2 as-number 200
[SwitchA-bgp-default] peer 193.1.1.2 as-number 200
[SwitchA-bgp-default] address-family ipv4 unicast
[SwitchA-bgp-default-ipv4] peer 192.1.1.2 enable
[SwitchA-bgp-default-ipv4] peer 193.1.1.2 enable
# Inject network 1.0.0.0/8 to the BGP routing table on Switch A.
[SwitchA-bgp-default-ipv4] network 1.0.0.0 8
[SwitchA-bgp-default-ipv4] quit
[SwitchA-bgp-default] quit
# Configure Switch B.
[SwitchB] bgp 200
[SwitchB-bgp-default] peer 192.1.1.1 as-number 100
[SwitchB-bgp-default] peer 194.1.1.1 as-number 200
[SwitchB-bgp-default] address-family ipv4 unicast
[SwitchB-bgp-default-ipv4] peer 192.1.1.1 enable
[SwitchB-bgp-default-ipv4] peer 194.1.1.1 enable
[SwitchB-bgp-default-ipv4] quit
[SwitchB-bgp-default] quit
# Configure Switch C.
[SwitchC] bgp 200
[SwitchC-bgp-default] peer 193.1.1.1 as-number 100
[SwitchC-bgp-default] peer 195.1.1.1 as-number 200
[SwitchC-bgp-default] address-family ipv4 unicast
[SwitchC-bgp-default-ipv4] peer 193.1.1.1 enable
[SwitchC-bgp-default-ipv4] peer 195.1.1.1 enable
[SwitchC-bgp-default-ipv4] quit
[SwitchC-bgp-default] quit
# Configure Switch D.
[SwitchD] bgp 200
[SwitchD-bgp-default] peer 194.1.1.2 as-number 200
[SwitchD-bgp-default] peer 195.1.1.2 as-number 200
[SwitchD-bgp-default] address-family ipv4 unicast
[SwitchD-bgp-default-ipv4] peer 194.1.1.2 enable
[SwitchD-bgp-default-ipv4] peer 195.1.1.2 enable
[SwitchD-bgp-default-ipv4] quit
[SwitchD-bgp-default] quit
4. Configure local preference for route 1.0.0.0/8, making Switch D give priority to the route learned from Switch C:
# Define IPv4 basic ACL 2000 on Switch C to permit route 1.0.0.0/8.
[SwitchC] acl basic 2000
[SwitchC-acl-ipv4-basic-2000] rule permit source 1.0.0.0 0.255.255.255
[SwitchC-acl-ipv4-basic-2000] quit
# Configure a routing policy named localpref on Switch C, setting the local preference of route 1.0.0.0/8 to 200 (the default is 100).
[SwitchC] route-policy localpref permit node 10
[SwitchC-route-policy-localpref-10] if-match ip address acl 2000
[SwitchC-route-policy-localpref-10] apply local-preference 200
[SwitchC-route-policy-localpref-10] quit
# Apply routing policy localpref to routes from peer 193.1.1.1.
[SwitchC] bgp 200
[SwitchC-bgp-default] address-family ipv4 unicast
[SwitchC-bgp-default-ipv4] peer 193.1.1.1 route-policy localpref import
[SwitchC-bgp-default-ipv4] quit
[SwitchC-bgp-default] quit
# Display the BGP routing table on Switch D.
[SwitchD] display bgp routing-table ipv4
Total number of routes: 2
BGP local router ID is 195.1.1.1
Status codes: * - valid, > - best, d - dampened, h - history,
s - suppressed, S - stale, i - internal, e - external
Origin: i - IGP, e - EGP, ? - incomplete
Network NextHop MED LocPrf PrefVal Path/Ogn
* >i 1.0.0.0 193.1.1.1 200 0 100i
* i 192.1.1.1 100 0 100i
Route 1.0.0.0/8 learned from Switch C is the optimal.
BGP GR configuration example
Network requirements
As shown in Figure 73, all switches run BGP. EBGP runs between Switch A and Switch B. IBGP runs between Switch B and Switch C.
Enable GR capability for BGP so that the communication between Switch A and Switch C is not affected when an active/standby switchover occurs on Switch B.
Configuration procedure
1. Configure Switch A:
# Configure IP addresses for interfaces. (Details not shown.)
# Configure the EBGP connection.
<SwitchA> system-view
[SwitchA] bgp 65008
[SwitchA-bgp-default] router-id 1.1.1.1
[SwitchA-bgp-default] peer 200.1.1.1 as-number 65009
# Enable GR capability for BGP.
[SwitchA-bgp-default] graceful-restart
# Inject network 8.0.0.0/8 to the BGP routing table.
[SwitchA-bgp-default] address-family ipv4
[SwitchA-bgp-default-ipv4] network 8.0.0.0
# Enable Switch A to exchange IPv4 unicast routing information with Switch B.
[SwitchA-bgp-default-ipv4] peer 200.1.1.1 enable
2. Configure Switch B:
# Configure IP addresses for interfaces. (Details not shown.)
# Configure the EBGP connection.
<SwitchB> system-view
[SwitchB] bgp 65009
[SwitchB-bgp-default] router-id 2.2.2.2
[SwitchB-bgp-default] peer 200.1.1.2 as-number 65008
# Configure the IBGP connection.
[SwitchB-bgp-default] peer 9.1.1.2 as-number 65009
# Enable GR capability for BGP.
[SwitchB-bgp-default] graceful-restart
# Inject networks 200.1.1.0/24 and 9.1.1.0/24 to the BGP routing table.
[SwitchB-bgp-default] address-family ipv4
[SwitchB-bgp-default-ipv4] network 200.1.1.0 24
[SwitchB-bgp-default-ipv4] network 9.1.1.0 24
# Enable Switch B to exchange IPv4 unicast routing information with Switch A and Switch C.
[SwitchB-bgp-default-ipv4] peer 200.1.1.2 enable
[SwitchB-bgp-default-ipv4] peer 9.1.1.2 enable
3. Configure Switch C:
# Configure IP addresses for interfaces. (Details not shown.)
# Configure the IBGP connection.
<SwitchC> system-view
[SwitchC] bgp 65009
[SwitchC-bgp-default] router-id 3.3.3.3
[SwitchC-bgp-default] peer 9.1.1.1 as-number 65009
# Enable GR capability for BGP.
[SwitchC-bgp-default] graceful-restart
# Enable Switch C to exchange IPv4 unicast routing information with Switch B.
[SwitchC-bgp-default-ipv4] peer 9.1.1.1 enable
Verifying the configuration
Ping Switch C on Switch A. Meanwhile, perform an active/standby switchover on Switch B. The ping operation is successful during the whole switchover process. (Details not shown.)
BFD for BGP configuration example
Network requirements
As shown in Figure 74, configure OSPF as the IGP in AS 200.
· Establish two IBGP connections between Switch A and Switch C. When both paths operate correctly, Switch C uses the path Switch A<—>Switch B<—>Switch C to exchange packets with network 1.1.1.0/24.
· Configure BFD over the path. When the path fails, BFD can quickly detect the failure and notify it to BGP. Then, the path Switch A<—>Switch D<—>Switch C takes effect immediately.
Table 19 Interface and IP address assignment
Device |
Interface |
IP address |
Device |
Interface |
IP address |
Switch A |
Vlan-int100 |
3.0.1.1/24 |
Switch C |
Vlan-int101 |
3.0.2.2/24 |
|
Vlan-int200 |
2.0.1.1/24 |
|
Vlan-int201 |
2.0.2.2/24 |
Switch B |
Vlan-int100 |
3.0.1.2/24 |
Switch D |
Vlan-int200 |
2.0.1.2/24 |
|
Vlan-int101 |
3.0.2.1/24 |
|
Vlan-int201 |
2.0.2.1/24 |
Configuration procedure
1. Configure IP addresses for interfaces. (Details not shown.)
2. Configure OSPF to ensure that Switch A and Switch C are reachable to each other. (Details not shown.)
3. Configure BGP on Switch A:
# Establish two IBGP connections to Switch C.
<SwitchA> system-view
[SwitchA] bgp 200
[SwitchA-bgp-default] peer 3.0.2.2 as-number 200
[SwitchA-bgp-default] peer 2.0.2.2 as-number 200
[SwitchA-bgp-default] address-family ipv4 unicast
[SwitchA-bgp-default-ipv4] peer 3.0.2.2 enable
[SwitchA-bgp-default-ipv4] peer 2.0.2.2 enable
[SwitchA-bgp-default-ipv4] quit
[SwitchA-bgp-default] quit
# Create IPv4 basic ACL 2000 to permit 1.1.1.0/24 to pass.
[SwitchA] acl basic 2000
[SwitchA-acl-ipv4-basic-2000] rule permit source 1.1.1.0 0.0.0.255
[SwitchA-acl-ipv4-basic-2000] quit
# Create two routing policies to set the MED for route 1.1.1.0/24. The policy apply_med_50 sets the MED to 50, and the policy apply_med_100 sets the MED to 100.
[SwitchA] route-policy apply_med_50 permit node 10
[SwitchA-route-policy-apply_med_50-10] if-match ip address acl 2000
[SwitchA-route-policy-apply_med_50-10] apply cost 50
[SwitchA-route-policy-apply_med_50-10] quit
[SwitchA] route-policy apply_med_100 permit node 10
[SwitchA-route-policy-apply_med_100-10] if-match ip address acl 2000
[SwitchA-route-policy-apply_med_100-10] apply cost 100
[SwitchA-route-policy-apply_med_100-10] quit
# Apply routing policy apply_med_50 to routes outgoing to peer 3.0.2.2, and apply routing policy apply_med_100 to routes outgoing to peer 2.0.2.2.
[SwitchA] bgp 200
[SwitchA-bgp-default] address-family ipv4 unicast
[SwitchA-bgp-default-ipv4] peer 3.0.2.2 route-policy apply_med_50 export
[SwitchA-bgp-default-ipv4] peer 2.0.2.2 route-policy apply_med_100 export
[SwitchA-bgp-default-ipv4] quit
# Enable BFD for peer 3.0.2.2.
[SwitchA-bgp-default] peer 3.0.2.2 bfd
[SwitchA-bgp-default] quit
4. Configure BGP on Switch C:
# Establish two IBGP connections to Switch A.
<SwitchC> system-view
[SwitchC] bgp 200
[SwitchC-bgp-default] peer 3.0.1.1 as-number 200
[SwitchC-bgp-default] peer 2.0.1.1 as-number 200
[SwitchC-bgp-default] address-family ipv4 unicast
[SwitchC-bgp-default-ipv4] peer 3.0.1.1 enable
[SwitchC-bgp-default-ipv4] peer 2.0.1.1 enable
[SwitchC-bgp-default-ipv4] quit
# Enable BFD for peer 3.0.1.1.
[SwitchC-bgp-default] peer 3.0.1.1 bfd
[SwitchC-bgp-default] quit
[SwitchC] quit
Verifying the configuration
# Display detailed BFD session information on Switch C.
<SwitchC> display bfd session verbose
Total Session Num: 1 Up Session Num: 1 Init Mode: Active
IPv4 Session Working Under Ctrl Mode:
Local Discr: 513 Remote Discr: 513
Source IP: 3.0.2.2 Destination IP: 3.0.1.1
Session State: Up Interface: N/A
Min Tx Inter: 500ms Act Tx Inter: 500ms
Min Rx Inter: 500ms Detect Inter: 2500ms
Rx Count: 135 Tx Count: 135
Connect Type: Indirect Running Up for: 00:00:58
Hold Time: 2457ms Auth mode: None
Detect Mode: Async Slot: 0
Protocol: BGP
Version: 1
Diag Info: No Diagnostic
The output shows that a BFD session has been established between Switch A and Switch C.
# Display BGP peer information on Switch C.
<SwitchC> display bgp peer ipv4
BGP local router ID: 3.3.3.3
Local AS number: 200
Total number of peers: 2 Peers in established state: 2
* - Dynamically created peer
Peer AS MsgRcvd MsgSent OutQ PrefRcv Up/Down State
2.0.1.1 200 4 5 0 0 00:01:55 Established
3.0.1.1 200 4 5 0 0 00:01:52 Established
The output shows that Switch C has established two BGP connections with Switch A, and both connections are in Established state.
# Display route 1.1.1.0/24 on Switch C.
<SwitchC> display ip routing-table 1.1.1.0 24 verbose
Summary count : 1
Destination: 1.1.1.0/24
Protocol: BGP Process ID: 0
SubProtID: 0x1 Age: 00h00m09s
Cost: 50 Preference: 255
IpPre: N/A QosLocalID: N/A
Tag: 0 State: Active Adv
OrigTblID: 0x1 OrigVrf: default-vrf
TableID: 0x2 OrigAs: 0
NibID: 0x15000001 LastAs: 0
AttrID: 0x1 Neighbor: 3.0.1.1
Flags: 0x10060 OrigNextHop: 3.0.1.1
Label: NULL RealNextHop: 3.0.2.1
BkLabel: NULL BkNextHop: N/A
Tunnel ID: Invalid Interface: Vlan-interface101
BkTunnel ID: Invalid BkInterface: N/A
FtnIndex: 0x0 TrafficIndex: N/A
Connector: N/A
The output shows that Switch C communicates with network 1.1.1.0/24 through the path Switch C<—>Switch B<—>Switch A.
# Break down the path Switch C<—>Switch B<—>Switch A and then display route 1.1.1.0/24 on Switch C.
<SwitchC> display ip routing-table 1.1.1.0 24 verbose
Summary count : 1
Destination: 1.1.1.0/24
Protocol: BGP Process ID: 0
SubProtID: 0x1 Age: 00h03m08s
Cost: 100 Preference: 255
IpPre: N/A QosLocalID: N/A
Tag: 0 State: Active Adv
OrigTblID: 0x1 OrigVrf: default-vrf
TableID: 0x2 OrigAs: 0
NibID: 0x15000000 LastAs: 0
AttrID: 0x0 Neighbor: 2.0.1.1
Flags: 0x10060 OrigNextHop: 2.0.1.1
Label: NULL RealNextHop: 2.0.2.1
BkLabel: NULL BkNextHop: N/A
Tunnel ID: Invalid Interface: Vlan-interface201
BkTunnel ID: Invalid BkInterface: N/A
FtnIndex: 0x0 TrafficIndex: N/A
Connector: N/A
The output shows that Switch C communicates with network 1.1.1.0/24 through the path Switch C<—>Switch D<—>Switch A.
BGP FRR configuration example
Network requirements
As shown in Figure 75, configure BGP FRR so that when Link B fails, BGP uses Link A to forward traffic.
Configuration procedure
1. Configure IP addresses for interfaces. (Details not shown.)
2. Configure OSPF in AS 200 to ensure connectivity among Switch B, Switch C, and Switch D. (Details not shown.)
3. Configure BGP connections:
# Configure Switch A to establish EBGP sessions to Switch B and Switch C, and advertise network 1.1.1.1/32.
<SwitchA> system-view
[SwitchA] bgp 100
[SwitchA-bgp-default] router-id 1.1.1.1
[SwitchA-bgp-default] peer 10.1.1.2 as-number 200
[SwitchA-bgp-default] peer 30.1.1.3 as-number 200
[SwitchA-bgp-default] address-family ipv4 unicast
[SwitchA-bgp-default-ipv4] peer 10.1.1.2 enable
[SwitchA-bgp-default-ipv4] peer 30.1.1.3 enable
[SwitchA-bgp-default-ipv4] network 1.1.1.1 32
# Configure Switch B to establish an EBGP session to Switch A, and an IBGP session to Switch D.
<SwitchB> system-view
[SwitchB] bgp 200
[SwitchB-bgp-default] router-id 2.2.2.2
[SwitchB-bgp-default] peer 10.1.1.1 as-number 100
[SwitchB-bgp-default] peer 4.4.4.4 as-number 200
[SwitchB-bgp-default] peer 4.4.4.4 connect-interface loopback 0
[SwitchB-bgp-default] address-family ipv4 unicast
[SwitchB-bgp-default-ipv4] peer 10.1.1.1 enable
[SwitchB-bgp-default-ipv4] peer 4.4.4.4 enable
[SwitchB-bgp-default-ipv4] peer 4.4.4.4 next-hop-local
[SwitchB-bgp-default-ipv4] quit
[SwitchB-bgp-default] quit
# Configure Switch C to establish an EBGP session to Switch A, and an IBGP session to Switch D.
<SwitchC> system-view
[SwitchC] bgp 200
[SwitchC-bgp-default] router-id 3.3.3.3
[SwitchC-bgp-default] peer 30.1.1.1 as-number 100
[SwitchC-bgp-default] peer 4.4.4.4 as-number 200
[SwitchC-bgp-default] peer 4.4.4.4 connect-interface loopback 0
[SwitchC-bgp-default] address-family ipv4 unicast
[SwitchC-bgp-default-ipv4] peer 30.1.1.1 enable
[SwitchC-bgp-default-ipv4] peer 4.4.4.4 enable
[SwitchC-bgp-default-ipv4] peer 4.4.4.4 next-hop-local
[SwitchC-bgp-default-ipv4] quit
[SwitchC-bgp-default] quit
# Configure Switch D to establish IBGP sessions to Switch B and Switch C, and advertise network 4.4.4.4/32.
<SwitchD> system-view
[SwitchD] bgp 200
[SwitchD-bgp-default] router-id 4.4.4.4
[SwitchD-bgp-default] peer 2.2.2.2 as-number 200
[SwitchD-bgp-default] peer 2.2.2.2 connect-interface loopback 0
[SwitchD-bgp-default] peer 3.3.3.3 as-number 200
[SwitchD-bgp-default] peer 3.3.3.3 connect-interface loopback 0
[SwitchD-bgp-default] address-family ipv4 unicast
[SwitchD-bgp-default-ipv4] peer 2.2.2.2 enable
[SwitchD-bgp-default-ipv4] peer 3.3.3.3 enable
[SwitchD-bgp-default-ipv4] network 4.4.4.4 32
4. Configure preferred values so Link B is used to forward traffic between Switch A and Switch D:
# Configure Switch A to set the preferred value to 100 for routes received from Switch B.
[SwitchA-bgp-default-ipv4] peer 10.1.1.2 preferred-value 100
[SwitchA-bgp-default-ipv4] quit
[SwitchA-bgp-default] quit
# Configure Switch D to set the preferred value to 100 for routes received from Switch B.
[SwitchD-bgp-default-ipv4] peer 2.2.2.2 preferred-value 100
[SwitchD-bgp-default-ipv4] quit
[SwitchD-bgp-default] quit
5. Configure BGP FRR:
# On Switch A, set the source address of BFD echo packets to 11.1.1.1.
[SwitchA] bfd echo-source-ip 11.1.1.1
# Create routing policy frr to set a backup next hop 30.1.1.3 (Switch C) for the route destined for 4.4.4.4/32.
[SwitchA] ip prefix-list abc index 10 permit 4.4.4.4 32
[SwitchA] route-policy frr permit node 10
[SwitchA-route-policy] if-match ip address prefix-list abc
[SwitchA-route-policy] apply fast-reroute backup-nexthop 30.1.1.3
[SwitchA-route-policy] quit
# Use echo-mode BFD to detect the connectivity to Switch D.
[SwitchA] bgp 100
[SwitchA-bgp-default] primary-path-detect bfd echo
# Apply the routing policy to BGP FRR for BGP IPv4 unicast address family.
[SwitchA-bgp-default] address-family ipv4 unicast
[SwitchA-bgp-default-ipv4] fast-reroute route-policy frr
[SwitchA-bgp-default-ipv4] quit
[SwitchA-bgp-default] quit
# On Switch D, set the source address of BFD echo packets to 44.1.1.1.
[SwitchD] bfd echo-source-ip 44.1.1.1
# Create routing policy frr to set a backup next hop 3.3.3.3 (Switch C) for the route destined for 1.1.1.1/32.
[SwitchD] ip prefix-list abc index 10 permit 1.1.1.1 32
[SwitchD] route-policy frr permit node 10
[SwitchD-route-policy] if-match ip address prefix-list abc
[SwitchD-route-policy] apply fast-reroute backup-nexthop 3.3.3.3
[SwitchD-route-policy] quit
# Use echo-mode BFD to detect the connectivity to Switch A.
[SwitchD] bgp 200
[SwitchD-bgp-default] primary-path-detect bfd echo
# Apply the routing policy to BGP FRR for BGP IPv4 unicast address family.
[SwitchD-bgp-default] address-family ipv4 unicast
[SwitchD-bgp-default-ipv4] fast-reroute route-policy frr
[SwitchD-bgp-default-ipv4] quit
[SwitchD-bgp-default] quit
Verifying the configuration
# Display detailed information about the route to 4.4.4.4/32 on Switch A. The output shows the backup next hop for the route.
[SwitchA] display ip routing-table 4.4.4.4 32 verbose
Summary count : 1
Destination: 4.4.4.4/32
Protocol: BGP Process ID: 0
SubProtID: 0x2 Age: 00h01m52s
Cost: 0 Preference: 255
IpPre: N/A QosLocalID: N/A
Tag: 0 State: Active Adv
OrigTblID: 0x0 OrigVrf: default-vrf
TableID: 0x2 OrigAs: 200
NibID: 0x15000003 LastAs: 200
AttrID: 0x5 Neighbor: 10.1.1.2
Flags: 0x10060 OrigNextHop: 10.1.1.2
Label: NULL RealNextHop: 10.1.1.2
BkLabel: NULL BkNextHop: 30.1.1.3
Tunnel ID: Invalid Interface: Vlan-interface 100
BkTunnel ID: Invalid BkInterface: Vlan-interface 200
FtnIndex: 0x0 TrafficIndex: N/A
Connector: N/A
# Display detailed information about the route to 1.1.1.1/32 on Switch D. The output shows the backup next hop for the route.
[SwitchD] display ip routing-table 1.1.1.1 32 verbose
Summary count : 1
Destination: 1.1.1.1/32
Protocol: BGP Process ID: 0
SubProtID: 0x1 Age: 00h00m36s
Cost: 0 Preference: 255
IpPre: N/A QosLocalID: N/A
Tag: 0 State: Active Adv
OrigTblID: 0x0 OrigVrf: default-vrf
TableID: 0x2 OrigAs: 100
NibID: 0x15000003 LastAs: 100
AttrID: 0x1 Neighbor: 2.2.2.2
Flags: 0x10060 OrigNextHop: 2.2.2.2
Label: NULL RealNextHop: 20.1.1.2
BkLabel: NULL BkNextHop: 40.1.1.3
Tunnel ID: Invalid Interface: Vlan-interface 101
BkTunnel ID: Invalid BkInterface: Vlan-interface 201
FtnIndex: 0x0 TrafficIndex: N/A
Connector: N/A
Multicast BGP configuration example
Network requirements
As shown in Figure 76, OSPF runs within AS 100 and AS 200 to ensure intra-AS connectivity. MBGP runs between the two ASs to exchange IPv4 unicast routes used for RPF check.
· Configure the Loopback 0 interface of Switch A and Switch B as the C-BSR and C-RP.
· Configure Switch A and Switch B to establish a Multicast Source Discovery Protocol (MSDP) peer relationship through MBGP, so that the receiver can receive multicast traffic from the source.
Table 20 Interface and IP address assignment
Device |
Interface |
IP address |
Device |
Interface |
IP address |
Source |
N/A |
10.110.1.100/24 |
Switch C |
Vlan-int200 |
10.110.2.1/24 |
Switch A |
Vlan-int100 |
10.110.1.1/24 |
|
Vlan-int102 |
192.168.2.2/24 |
|
Vlan-int101 |
192.168.1.1/24 |
|
Vlan-int104 |
192.168.4.1/24 |
|
Loop0 |
1.1.1.1/32 |
|
Loop0 |
3.3.3.3/32 |
Switch B |
Vlan-int101 |
192.168.1.2/24 |
Switch D |
Vlan-int103 |
192.168.3.2/24 |
|
Vlan-int102 |
192.168.2.1/24 |
|
Vlan-int104 |
192.168.4.2/24 |
|
Vlan-int103 |
192.168.3.1/24 |
|
Loop0 |
4.4.4.4/32 |
|
Loop0 |
2.2.2.2/32 |
|
|
|
Configuration procedure
1. Configure IP addresses for interfaces and configure OSPF (this example uses OSPF process 1) in AS 200 to ensure intra-AS connectivity. (Details not shown.)
2. Enable IP multicast routing, PIM-SM, and IGMP, and configure BSR boundaries:
# On Switch A, enable multicast routing globally, and enable PIM-SM on interfaces.
<SwitchA> system-view
[SwitchA] multicast routing
[SwitchA-mrib] quit
[SwitchA] interface vlan-interface 100
[SwitchA-Vlan-interface100] pim sm
[SwitchA-Vlan-interface100] quit
[SwitchA] interface vlan-interface 101
[SwitchA-Vlan-interface101] pim sm
[SwitchA-Vlan-interface101] quit
# Configure Switch B and Switch D in the same way that Switch A was configured.
# On Switch C, enable multicast routing globally.
<SwitchC> system-view
[SwitchC] multicast routing
[SwitchA-mrib] quit
# Enable PIM-SM on interfaces, and enable IGMP on VLAN-interface 200.
[SwitchC] interface vlan-interface 102
[SwitchC-Vlan-interface102] pim sm
[SwitchC-Vlan-interface102] quit
[SwitchC] interface vlan-interface 104
[SwitchC-Vlan-interface104] pim sm
[SwitchC-Vlan-interface104] quit
[SwitchC] interface vlan-interface 200
[SwitchC-Vlan-interface200] pim sm
[SwitchC-Vlan-interface200] igmp enable
[SwitchC-Vlan-interface200] quit
# Configure the BSR boundary on Switch A.
[SwitchA] interface vlan-interface 101
[SwitchA-Vlan-interface101] pim bsr-boundary
[SwitchA-Vlan-interface101] quit
# Configure the BSR boundary on Switch B.
[SwitchB] interface vlan-interface 101
[SwitchB-Vlan-interface101] pim bsr-boundary
[SwitchB-Vlan-interface101] quit
3. Configure Loopback 0, C-BSR, and C-RP:
# Configure the Loopback 0 interface and specify it as the C-BSR and C-RP on Switch A.
[SwitchA] interface loopback 0
[SwitchA-LoopBack0] ip address 1.1.1.1 32
[SwitchA-LoopBack0] pim sm
[SwitchA-LoopBack0] quit
[SwitchA] pim
[SwitchA-pim] c-bsr 1.1.1.1
[SwitchA-pim] c-rp 1.1.1.1
[SwitchA-pim] quit
# Configure the Loopback 0 interface and specify it as the C-BSR and C-RP on Switch B.
[SwitchB] interface loopback 0
[SwitchB-LoopBack0] ip address 2.2.2.2 32
[SwitchB-LoopBack0] pim sm
[SwitchB-LoopBack0] quit
[SwitchB] pim
[SwitchB-pim] c-bsr 2.2.2.2
[SwitchB-pim] c-rp 2.2.2.2
[SwitchB-pim] quit
4. Configure BGP to establish BGP IPv4 multicast peers and redistribute routes:
# On Switch A, establish an EBGP session to Switch B.
[SwitchA] bgp 100
[SwitchA-bgp-default] router-id 1.1.1.1
[SwitchA-bgp-default] peer 192.168.1.2 as-number 200
# Enable exchange of IPv4 unicast routes used for RPF check with Switch B.
[SwitchA-bgp-default] address-family ipv4 multicast
[SwitchA-bgp-default-mul-ipv4] peer 192.168.1.2 enable
# Redistribute direct routes into BGP.
[SwitchA-bgp-default-mul-ipv4] import-route direct
[SwitchA-bgp-default-mul-ipv4] quit
[SwitchA-bgp-default] quit
# On Switch B, establish an EBGP session to Switch A.
[SwitchB] bgp 200
[SwitchB-bgp-default] router-id 2.2.2.2
[SwitchB-bgp-default] peer 192.168.1.1 as-number 100
# Enable exchange of IPv4 unicast routes used for RPF check with Switch B.
[SwitchB-bgp-default] address-family ipv4 multicast
[SwitchB-bgp-default-mul-ipv4] peer 192.168.1.1 enable
# Redistribute OSPF routes into BGP.
[SwitchB-bgp-default-mul-ipv4] import-route ospf 1
[SwitchB-bgp-default-mul-ipv4] quit
[SwitchB-bgp-default] quit
5. Configure MSDP peers:
# Configure an MSDP peer on Switch A.
[SwitchA] msdp
[SwitchA-msdp] peer 192.168.1.2 connect-interface vlan-interface 101
[SwitchA-msdp] quit
# Configure an MSDP peer on Switch B.
[SwitchB] msdp
[SwitchB-msdp] peer 192.168.1.1 connect-interface vlan-interface 101
[SwitchB-msdp] quit
Verifying the configuration
# Verify the BGP IPv4 multicast peer information on Switch B.
[SwitchB] display bgp peer ipv4 multicast
BGP local router ID : 2.2.2.2
Local AS number : 200
Total number of peers : 3 Peers in established state : 3
Peer AS MsgRcvd MsgSent OutQ PrefRcv Up/Down State
192.168.1.1 100 56 56 0 0 00:40:54 Established
# Verify the MSDP peer information on Switch B.
[SwitchB] display msdp brief
Configured Established Listen Connect Shutdown Disabled
1 1 0 0 0 0
Peer address State Up/Down time AS SA count Reset count
192.168.1.1 Established 00:07:17 100 1 0
Dynamic BGP peer configuration example
Network requirements
As shown in Figure 77, Switch A needs to establish IBGP peer relationships with Switch B, Switch C, and Switch D in network 10.1.0.0/16. Configure dynamic BGP peers to simplify the configuration.
Configure Switch A as the route reflector, and configure Switch B, Switch C, and Switch D as its clients.
Configuration procedure
1. Configure IP addresses for interfaces. (Details not shown.)
2. Configure IBGP peer relationship:
# Configure Switch A to establish dynamic BGP peer relationships with switches in network 10.1.0.0/16.
<SwitchA> system-view
[SwitchA] bgp 200
[SwitchA-bgp-default] router-id 1.1.1.1
[SwitchA-bgp-default] peer 10.1.0.0 16 as-number 200
[SwitchA-bgp-default] address-family ipv4
[SwitchA-bgp-default-ipv4] peer 10.1.0.0 16 enable
# Configure Switch B to establish an IBGP peer relationship with Switch A.
<SwitchB> system-view
[SwitchB] bgp 200
[SwitchB-bgp-default] router-id 2.2.2.2
[SwitchB-bgp-default] peer 10.1.1.1 as-number 200
[SwitchB-bgp-default] address-family ipv4
[SwitchB-bgp-default-ipv4] peer 10.1.1.1 enable
# Configure Switch C to establish an IBGP peer relationship with Switch A.
<SwitchC> system-view
[SwitchC] bgp 200
[SwitchC-bgp-default] router-id 3.3.3.3
[SwitchC-bgp-default] peer 10.1.2.1 as-number 200
[SwitchC-bgp-default] address-family ipv4
[SwitchC-bgp-default-ipv4] peer 10.1.2.1 enable
# Configure Switch D to establish an IBGP peer relationship with Switch A.
<SwitchD> system-view
[SwitchD] bgp 200
[SwitchD-bgp-default] router-id 4.4.4.4
[SwitchD-bgp-default] peer 10.1.3.1 as-number 200
[SwitchD-bgp-default] address-family ipv4
[SwitchD-bgp-default-ipv4] peer 10.1.3.1 enable
# Display BGP peer information on Switch A. The output shows that Switch A has established IBGP peer relationships with Switch B, Switch C, and Switch D.
[SwitchA] display bgp peer ipv4
BGP local router ID : 1.1.1.1
Local AS number : 200
Total number of peers : 3 Peers in established state : 3
* - Dynamically created peer
Peer AS MsgRcvd MsgSent OutQ PrefRcv Up/Down State
*10.1.1.2 200 7 10 0 0 00:06:09 Established
*10.1.2.2 200 7 10 0 0 00:06:09 Established
*10.1.3.2 200 7 10 0 0 00:06:09 Established
3. Configure Switch A as the route reflector, and configure peers in network 10.1.0.0/16 as its clients.
[SwitchA-bgp-default-ipv4] peer 10.1.0.0 16 reflect-client
4. Configure Switch C to advertise network 9.1.1.0/24.
[SwitchC-bgp-default-ipv4] network 9.1.1.0 24
Verifying the configuration
# Verify that route 9.1.1.0/24 exists in the BGP routing table on Switch A, Switch B, and Switch D. This example uses Switch A.
[SwitchA-bgp-default] display bgp routing-table ipv4
Total Number of Routes: 1
BGP Local router ID is 1.1.1.1
Status codes: * - valid, > - best, d - dampened, h - history,
s - suppressed, S - stale, i - internal, e - external
Origin: i - IGP, e - EGP, ? - incomplete
Network NextHop MED LocPrf PrefVal Path/Ogn
* i 9.1.1.0/24 10.1.2.2 0 100 0 ?
BGP LS configuration example
Network requirements
As shown in Figure 78, all switches run BGP. Run IBGP between Switch A and Switch B, between Switch B and Switch C, and between Switch B and Switch D.
Configure Switch B as a route reflector with client Switch A to allow Switch A to learn LS information advertised by Switch C and Switch D.
Configuration procedure
1. Configure IP addresses for interfaces and configure OSPF on Switch C and Switch D. (Details not shown.)
2. Configure BGP connections:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] bgp 100
[SwitchA-bgp-default] peer 192.1.1.2 as-number 100
[SwitchA-bgp-default] address-family link-state
[SwitchA-bgp-default-ls] peer 192.1.1.2 enable
[SwitchA-bgp-default-ls] quit
[SwitchA-bgp-default] quit
# Configure Switch B.
<SwitchB> system-view
[SwitchB] bgp 100
[SwitchB-bgp-default] peer 192.1.1.1 as-number 100
[SwitchB-bgp-default] peer 193.1.1.1 as-number 100
[SwitchB-bgp-default] peer 194.1.1.1 as-number 100
[SwitchB-bgp-default] address-family link-state
[SwitchB-bgp-default-ls] peer 192.1.1.1 enable
[SwitchB-bgp-default-ls] peer 193.1.1.1 enable
[SwitchB-bgp-default-ls] peer 194.1.1.1 enable
[SwitchB-bgp-default-ls] quit
[SwitchB-bgp-default] quit
# Configure Switch C.
<SwitchC> system-view
[SwitchC] bgp 100
[SwitchC-bgp-default] peer 193.1.1.2 as-number 100
[SwitchC-bgp-default] address-family link-state
[SwitchC-bgp-default-ls] peer 193.1.1.2 enable
[SwitchC-bgp-default-ls] quit
[SwitchC-bgp-default] quit
[SwitchC] ospf
[SwitchC-ospf-1] distribute bgp-ls
[SwitchC-ospf-1] area 0
[SwitchC-ospf-1-area-0.0.0.0] network 0.0.0.0 0.0.0.0
[SwitchC-ospf-1-area-0.0.0.0] quit
[SwitchC-ospf-1] quit
# Configure Switch D.
<SwitchD> system-view
[SwitchD] bgp 100
[SwitchD-bgp-default] peer 194.1.1.2 as-number 100
[SwitchD-bgp-default] address-family link-state
[SwitchD-bgp-default-ls] peer 194.1.1.2 enable
[SwitchD-bgp-default-ls] quit
[SwitchD-bgp-default] quit
[SwitchD] ospf
[SwitchD-ospf-1] distribute bgp-ls
[SwitchD-ospf-1] area 0
[SwitchD-ospf-1-area-0.0.0.0] network 0.0.0.0 0.0.0.0
[SwitchD-ospf-1-area-0.0.0.0] quit
[SwitchD-ospf-1] quit
3. Configure Switch B as the route reflector.
[SwitchB] bgp 200
[SwitchB-bgp-default] address-family link-state
[SwitchB-bgp-default-ls] peer 192.1.1.1 reflect-client
[SwitchB-bgp-default-ls] quit
[SwitchB-bgp-default] quit
Verifying the configuration
# Verify that Switch A has learned LS information advertised by Switch C and Switch D.
[SwitchA] display bgp link-state
Total number of routes: 4
BGP local Switch ID is 192.1.1.1
Status codes: * - valid, > - best, d - dampened, h - history,
s - suppressed, S - stale, i - internal, e - external
Origin: i - IGP, e - EGP, ? - incomplete
Prefix codes: E link, V node, T IP reacheable route, u/U unknown,
I Identifier, N local node, R remote node, L link, P prefix,
L1/L2 ISIS level-1/level-2, O OSPF, D direct, S static,
a area-ID, , l link-ID, t topology-ID, s ISO-ID,
c confed-ID/ASN, b bgp-identifier, r Switch-ID,
i if-address, n nbr-address, o OSPF Route-type, p IP-prefix
d designated Switch address
i Network : [V][O][I0x0][N[c100][b193.1.1.1][a0.0.0.0][r193.1.1.1]]/376
NextHop : 193.1.1.1 LocPrf : 100
PrefVal : 0 OutLabel : NULL
MED :
Path/Ogn: i
i Network : [V][O][I0x0][N[c100][b194.1.1.1][a0.0.0.0][r194.1.1.1]]/376
NextHop : 194.1.1.1 LocPrf : 100
PrefVal : 0 OutLabel : NULL
MED :
Path/Ogn: i
i Network : [T][O][I0x0][N[c100][b193.1.1.1][a0.0.0.0][r193.1.1.1]][P[o0x1][p193.1.1.0/24]]/480
NextHop : 193.1.1.1 LocPrf : 100
PrefVal : 0 OutLabel : NULL
MED :
Path/Ogn: i
i Network : [T][O][I0x0][N[c100][b194.1.1.1][a0.0.0.0][r194.1.1.1]][P[o0x1][p194.1.1.0/24]]/480
NextHop : 194.1.1.1 LocPrf : 100
PrefVal : 0 OutLabel : NULL
MED :
Path/Ogn: i
IPv6 BGP configuration examples
IPv6 BGP basic configuration example
Network requirements
As shown in Figure 79, all switches run BGP. Run EBGP between Switch A and Switch B, and run IBGP between Switch B and Switch C to allow Switch C to access network 50::/64 connected to Switch A.
Configuration procedure
1. Configure IP addresses for interfaces. (Details not shown.)
2. Configure IBGP:
# Configure Switch B.
<SwitchB> system-view
[SwitchB] bgp 65009
[SwitchB-bgp-default] router-id 2.2.2.2
[SwitchB-bgp-default] peer 9::2 as-number 65009
[SwitchB-bgp-default] address-family ipv6
[SwitchB-bgp-default-ipv6] peer 9::2 enable
[SwitchB-bgp-default-ipv6] quit
# Configure Switch C.
<SwitchC> system-view
[SwitchC] bgp 65009
[SwitchC-bgp-default] router-id 3.3.3.3
[SwitchC-bgp-default] peer 9::1 as-number 65009
[SwitchC-bgp-default] address-family ipv6
[SwitchC-bgp-default-ipv6] peer 9::1 enable
3. Configure EBGP:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] bgp 65008
[SwitchA-bgp-default] router-id 1.1.1.1
[SwitchA-bgp-default] peer 10::1 as-number 65009
[SwitchA-bgp-default] address-family ipv6
[SwitchA-bgp-default-ipv6] peer 10::1 enable
# Configure Switch B.
[SwitchB-bgp-default] peer 10::2 as-number 65008
[SwitchB-bgp-default] address-family ipv6
[SwitchB-bgp-default-ipv6] peer 10::2 enable
4. Inject network routes to the BGP routing table:
# Configure Switch A.
[SwitchA-bgp-default-ipv6] network 10:: 64
[SwitchA-bgp-default-ipv6] network 50:: 64
[SwitchA-bgp-default-ipv6] quit
[SwitchA-bgp-default] quit
# Configure Switch B.
[SwitchB-bgp-default-ipv6] network 10:: 64
[SwitchB-bgp-default-ipv6] network 9:: 64
[SwitchB-bgp-default-ipv6] quit
[SwitchB-bgp-default] quit
# Configure Switch C.
[SwitchC-bgp-default-ipv6] network 9:: 64
[SwitchC-bgp-default-ipv6] quit
[SwitchC-bgp-default] quit
Verifying the configuration
# Display IPv6 BGP peer information on Switch B.
[SwitchB] display bgp peer ipv6
BGP local router ID: 2.2.2.2
Local AS number: 65009
Total number of peers: 2 Peers in established state: 2
* - Dynamically created peer
Peer AS MsgRcvd MsgSent OutQ PrefRcv Up/Down State
9::2 65009 41 43 0 1 00:29:00 Established
10::2 65008 38 38 0 2 00:27:20 Established
The output shows that Switch A and Switch B have established an EBGP connection, and Switch B and Switch C have established an IBGP connection.
# Display IPv6 BGP routing table information on Switch A.
[SwitchA] display bgp routing-table ipv6
Total number of routes: 4
BGP local router ID is 1.1.1.1
Status codes: * - valid, > - best, d - dampened, h - history,
s - suppressed, S - stale, i - internal, e - external
Origin: i - IGP, e - EGP, ? - incomplete
* >e Network : 9:: PrefixLen : 64
NextHop : 10::1 LocPrf :
PrefVal : 0 OutLabel : NULL
MED : 0
Path/Ogn: 65009i
* > Network : 10:: PrefixLen : 64
NextHop : :: LocPrf :
PrefVal : 32768 OutLabel : NULL
MED : 0
Path/Ogn: i
* e Network : 10:: PrefixLen : 64
NextHop : 10::1 LocPrf :
PrefVal : 0 OutLabel : NULL
MED : 0
Path/Ogn: 65009i
* > Network : 50:: PrefixLen : 64
NextHop : :: LocPrf :
PrefVal : 32768 OutLabel : NULL
MED : 0
Path/Ogn: i
The output shows that Switch A has learned routing information of AS 65009.
# Display IPv6 BGP routing table information on Switch C.
[SwitchC] display bgp routing-table ipv6
Total number of routes: 4
BGP local router ID is 3.3.3.3
Status codes: * - valid, > - best, d - dampened, h - history,
s - suppressed, S - stale, i - internal, e - external
Origin: i - IGP, e - EGP, ? - incomplete
* > Network : 9:: PrefixLen : 64
NextHop : :: LocPrf :
PrefVal : 32768 OutLabel : NULL
MED : 0
Path/Ogn: i
* i Network : 9:: PrefixLen : 64
NextHop : 9::1 LocPrf : 100
PrefVal : 0 OutLabel : NULL
MED : 0
Path/Ogn: i
* >i Network : 10:: PrefixLen : 64
NextHop : 9::1 LocPrf : 100
PrefVal : 0 OutLabel : NULL
MED : 0
Path/Ogn: i
* >i Network : 50:: PrefixLen : 64
NextHop : 10::2 LocPrf : 100
PrefVal : 0 OutLabel : NULL
MED : 0
Path/Ogn: 65008i
The output shows that Switch C has learned the route 50::/64.
# Verify that Switch C can ping hosts on network 50::/64. (Details not shown.)
IPv6 BGP route reflector configuration example
Network requirements
As shown in Figure 80, run EBGP between Switch A and Switch B, run IBGP between Switch C and Switch B, and between Switch C and Switch D.
Configure Switch C as a route reflector with clients Switch B and Switch D.
Configuration procedure
1. Configure IPv6 addresses for interfaces and IPv4 addresses for loopback interfaces. (Details not shown.)
2. Configure IBGP and EBGP connections and advertise network routes through IPv6 BGP:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] bgp 100
[SwitchA-bgp-default] router-id 1.1.1.1
[SwitchA-bgp-default] peer 100::2 as-number 200
[SwitchA-bgp-default] address-family ipv6
[SwitchA-bgp-default-ipv6] peer 100::2 enable
[SwitchA-bgp-default-ipv6] network 1:: 64
[SwitchA-bgp-default-ipv6] network 100:: 96
[SwitchA-bgp-default-ipv6] quit
[SwitchA-bgp-default] quit
# Configure Switch B.
<SwitchB> system-view
[SwitchB] bgp 200
[SwitchB-bgp-default] router-id 2.2.2.2
[SwitchB-bgp-default] peer 100::1 as-number 100
[SwitchB-bgp-default] peer 101::1 as-number 200
[SwitchB-bgp-default] address-family ipv6
[SwitchB-bgp-default-ipv6] peer 100::1 enable
[SwitchB-bgp-default-ipv6] peer 101::1 enable
[SwitchB-bgp-default-ipv6] peer 101::1 next-hop-local
[SwitchB-bgp-default-ipv6] network 100:: 96
[SwitchB-bgp-default-ipv6] network 101:: 96
[SwitchB-bgp-default-ipv6] quit
[SwitchB-bgp-default] quit
# Configure Switch C.
<SwitchC> system-view
[SwitchC] bgp 200
[SwitchC-bgp-default] router-id 3.3.3.3
[SwitchC-bgp-default] peer 101::2 as-number 200
[SwitchC-bgp-default] peer 102::2 as-number 200
[SwitchC-bgp-default] address-family ipv6
[SwitchC-bgp-default-ipv6] peer 101::2 enable
[SwitchC-bgp-default-ipv6] peer 102::2 enable
[SwitchC-bgp-default-ipv6] network 101:: 96
[SwitchC-bgp-default-ipv6] network 102:: 96
# Configure Switch D.
<SwitchD> system-view
[SwitchD] bgp 200
[SwitchD-bgp-default] router-id 4.4.4.4
[SwitchD-bgp-default] peer 102::1 as-number 200
[SwitchD-bgp-default] address-family ipv6
[SwitchD-bgp-default-ipv6] peer 102::1 enable
[SwitchD-bgp-default-ipv6] network 102:: 96
3. Configure Switch C as a route reflector, and configure Switch B and Switch D as its clients.
[SwitchC-bgp-default-ipv6] peer 101::2 reflect-client
[SwitchC-bgp-default-ipv6] peer 102::2 reflect-client
[SwitchC-bgp-default-ipv6] quit
[SwitchC-bgp-default] quit
Verifying the configuration
# Execute the display bgp routing-table ipv6 command on Switch D.
[SwitchD] display bgp routing-table ipv6
Total number of routes: 5
BGP local router ID is 4.4.4.4
Status codes: * - valid, > - best, d - dampened, h - history,
s - suppressed, S - stale, i - internal, e - external
Origin: i - IGP, e - EGP, ? - incomplete
* >i Network : 1:: PrefixLen : 64
NextHop : 101::2 LocPrf : 100
PrefVal : 0 OutLabel : NULL
MED : 0
Path/Ogn: 100i
* >i Network : 100:: PrefixLen : 96
NextHop : 101::2 LocPrf : 100
PrefVal : 0 OutLabel : NULL
MED : 0
Path/Ogn: i
* >i Network : 101:: PrefixLen : 96
NextHop : 102::1 LocPrf : 100
PrefVal : 0 OutLabel : NULL
MED : 0
Path/Ogn: i
* > Network : 102:: PrefixLen : 96
NextHop : :: LocPrf :
PrefVal : 32768 OutLabel : NULL
MED : 0
Path/Ogn: i
* i Network : 102:: PrefixLen : 96
NextHop : 102::1 LocPrf : 100
PrefVal : 0 OutLabel : NULL
MED : 0
Path/Ogn: i
The output shows that Switch D has learned the network 1::/64 from Switch C through route reflection.
6PE configuration example
Network requirements
As shown in Figure 81, use 6PE to connect two isolated IPv6 networks over an IPv4/MPLS network.
· The ISP uses OSPF as the IGP.
· PE 1 and PE 2 are edge devices of the ISP, and establish an IPv4 IBGP connection between them.
· CE 1 and CE 2 are edge devices of the IPv6 networks, and they connect the IPv6 networks to the ISP.
· A CE and a PE exchange IPv6 packets through IPv6 static routing.
Configuration procedure
1. Configure IPv6 addresses and IPv4 addresses for interfaces. (Details not shown.)
2. Configure PE 1:
# Enable LDP globally, and configure the LSP generation policy.
<PE1> system-view
[PE1] mpls lsr-id 2.2.2.2
[PE1] mpls ldp
[PE1-ldp] lsp-trigger all
[PE1-ldp] quit
# Enable MPLS and LDP on VLAN-interface 30.
[PE1] interface vlan-interface 30
[PE1-Vlan-interface30] mpls enable
[PE1-Vlan-interface30] mpls ldp enable
[PE1-Vlan-interface30] quit
# Configure IBGP, enable the peer's 6PE capabilities, and redistribute IPv6 direct and static routes.
[PE1] bgp 65100
[PE1-bgp-default] router-id 2.2.2.2
[PE1-bgp-default] peer 3.3.3.3 as-number 65100
[PE1-bgp-default] peer 3.3.3.3 connect-interface loopback 0
[PE1-bgp-default] address-family ipv6
[PE1-bgp-default-ipv6] import-route direct
[PE1-bgp-default-ipv6] import-route static
[PE1-bgp-default-ipv6] peer 3.3.3.3 enable
[PE1-bgp-default-ipv6] peer 3.3.3.3 label-route-capability
[PE1-bgp-default-ipv6] quit
[PE1-bgp-default] quit
# Configure a static route to CE 1.
[PE1] ipv6 route-static 1::1 128 10::1
# Configure OSPF for the ISP.
[PE1] ospf
[PE1-ospf-1] area 0
[PE1-ospf-1-area-0.0.0.0] network 2.2.2.2 0.0.0.0
[PE1-ospf-1-area-0.0.0.0] network 1.1.0.0 0.0.255.255
[PE1-ospf-1-area-0.0.0.0] quit
[PE1-ospf-1] quit
3. Configure PE 2:
# Enable LDP globally, and configure the LSP generation policy.
<PE2> system-view
[PE2] mpls lsr-id 3.3.3.3
[PE2] mpls ldp
[PE2-mpls-ldp] lsp-trigger all
[PE2-mpls-ldp] quit
# Enable MPLS and LDP on VLAN-interface 30.
[PE2] interface vlan-interface 30
[PE2-Vlan-interface30] mpls enable
[PE2-Vlan-interface30] mpls ldp enable
[PE2-Vlan-interface30] quit
# Configure IBGP, enable the peer's 6PE capabilities, and redistribute IPv6 direct and static routes.
[PE2] bgp 65100
[PE2-bgp-default] router-id 3.3.3.3
[PE2-bgp-default] peer 2.2.2.2 as-number 65100
[PE2-bgp-default] peer 2.2.2.2 connect-interface loopback 0
[PE2-bgp-default] address-family ipv6
[PE2-bgp-default-ipv6] import-route direct
[PE2-bgp-default-ipv6] import-route static
[PE2-bgp-default-ipv6] peer 2.2.2.2 enable
[PE2-bgp-default-ipv6] peer 2.2.2.2 label-route-capability
[PE2-bgp-default-ipv6] quit
[PE2-bgp-default] quit
# Configure the static route to CE 2.
[PE2] ipv6 route-static 4::4 128 20::1
# Configure OSPF for the ISP.
[PE2] ospf
[PE2-ospf-1] area 0
[PE2-ospf-1-area-0.0.0.0] network 3.3.3.3 0.0.0.0
[PE2-ospf-1-area-0.0.0.0] network 1.1.0.0 0.0.255.255
[PE2-ospf-1-area-0.0.0.0] quit
[PE2-ospf-1] quit
4. Configure a static route on CE 1, with PE 1 as the default next hop.
<CE1> system-view
[CE1] ipv6 route-static :: 0 10::2
5. Configure a static route on CE 2, with PE 2 as the default next hop.
<CE2> system-view
[CE2] ipv6 route-static :: 0 20::2
Verifying the configuration
# Display the IPv6 BGP routing tables on PE 1 and PE 2. The output shows that each of them has two IPv6 network routes. The following shows the output on PE 1:
[PE1] display bgp routing-table ipv6
Total number of routes: 5
BGP local router ID is 2.2.2.2
Status codes: * - valid, > - best, d - dampened, h - history,
s - suppressed, S - stale, i - internal, e - external
Origin: i - IGP, e - EGP, ? - incomplete
* > Network : 1::1 PrefixLen : 128
NextHop : 10::1 LocPrf :
PrefVal : 32768 OutLabel : NULL
MED : 0
Path/Ogn: ?
* >i Network : 4::4 PrefixLen : 128
NextHop : ::FFFF:3.3.3.3 LocPrf : 100
PrefVal : 0 OutLabel : 1279
MED : 0
Path/Ogn: ?
* > Network : 10:: PrefixLen : 64
NextHop : :: LocPrf :
PrefVal : 32768 OutLabel : NULL
MED : 0
Path/Ogn: ?
* > Network : 10::2 PrefixLen : 128
NextHop : ::1 LocPrf :
PrefVal : 32768 OutLabel : NULL
MED : 0
Path/Ogn: ?
* >i Network : 20:: PrefixLen : 64
NextHop : ::FFFF:3.3.3.3 LocPrf : 100
PrefVal : 0 OutLabel : 1278
MED : 0
Path/Ogn: ?
# Verify that CE 1 can ping the IPv6 address 4::4 (loopback interface address) of CE 2. (Details not shown.)
BFD for IPv6 BGP configuration example
Network requirements
As shown in Figure 82, configure OSPFv3 as the IGP in AS 200.
· Establish two IBGP connections between Switch A and Switch C. When both paths operate correctly, Switch C uses the path Switch A<—>Switch B<—>Switch C to exchange packets with network 1200::0/64.
· Configure BFD over the path. When the path fails, BFD can quickly detect the failure and notify it to IPv6 BGP. Then, the path Switch A<—>Switch D<—>Switch C takes effect immediately.
Table 21 Interface and IP address assignment
Device |
Interface |
IP address |
Device |
Interface |
IP address |
Switch A |
Vlan-int100 |
3000::1/64 |
Switch C |
Vlan-int101 |
3001::3/64 |
|
Vlan-int200 |
2000::1/64 |
|
Vlan-int201 |
2001::3/64 |
Switch B |
Vlan-int100 |
3000::2/64 |
Switch D |
Vlan-int200 |
2000::2/64 |
|
Vlan-int101 |
3001::2/64 |
|
Vlan-int201 |
2001::2/64 |
Configuration procedure
1. Configure IPv6 addresses for interfaces. (Details not shown.)
2. Configure OSPFv3 so that Switch A and Switch C can reach each other. (Details not shown.)
3. Configure IPv6 BGP on Switch A:
# Establish two IBGP connections to Switch C.
<SwitchA> system-view
[SwitchA] bgp 200
[SwitchA-bgp-default] router-id 1.1.1.1
[SwitchA-bgp-default] peer 3001::3 as-number 200
[SwitchA-bgp-default] peer 2001::3 as-number 200
[SwitchA-bgp-default] address-family ipv6
[SwitchA-bgp-default-ipv6] peer 3001::3 enable
[SwitchA-bgp-default-ipv6] peer 2001::3 enable
[SwitchA-bgp-default-ipv6] quit
# Create IPv6 basic ACL 2000 to permit 1200::0/64 to pass.
[SwitchA] acl ipv6 basic 2000
[SwitchA-acl-ipv6-basic-2000] rule permit source 1200:: 64
[SwitchA-acl-ipv6-basic-2000] quit
# Create two routing policies to set the MED for route 1200::0/64. The policy apply_med_50 sets the MED to 50, and the policy apply_med_100 sets the MED to 100.
[SwitchA] route-policy apply_med_50 permit node 10
[SwitchA-route-policy-apply_med_50-10] if-match ipv6 address acl 2000
[SwitchA-route-policy-apply_med_50-10] apply cost 50
[SwitchA-route-policy-apply_med_50-10] quit
[SwitchA] route-policy apply_med_100 permit node 10
[SwitchA-route-policy-apply_med_100-10] if-match ipv6 address acl 2000
[SwitchA-route-policy-apply_med_100-10] apply cost 100
[SwitchA-route-policy-apply_med_100-10] quit
# Apply routing policy apply_med_50 to routes outgoing to peer 3001::3, and apply routing policy apply_med_100 to routes outgoing to peer 2001::3.
[SwitchA] bgp 200
[SwitchA-bgp-default] address-family ipv6 unicast
[SwitchA-bgp-default-ipv6] peer 3001::3 route-policy apply_med_50 export
[SwitchA-bgp-default-ipv6] peer 2001::3 route-policy apply_med_100 export
[SwitchA-bgp-default-ipv6] quit
# Enable BFD for peer 3001::3.
[SwitchA-bgp-default] peer 3001::3 bfd
[SwitchA-bgp-default] quit
4. Configure IPv6 BGP on Switch C:
# Establish two IBGP connections to Switch A.
<SwitchC> system-view
[SwitchC] bgp 200
[SwitchC-bgp-default] router-id 3.3.3.3
[SwitchC-bgp-default] peer 3000::1 as-number 200
[SwitchC-bgp-default] peer 2000::1 as-number 200
[SwitchC-bgp-default] address-family ipv6
[SwitchC-bgp-default-ipv6] peer 3000::1 enable
[SwitchC-bgp-default-ipv6] peer 2000::1 enable
[SwitchC-bgp-default-ipv6] quit
# Enable BFD for peer 3001::1.
[SwitchC-bgp-default] peer 3000::1 bfd
[SwitchC-bgp-default] quit
[SwitchC] quit
Verifying the configuration
# Display detailed BFD session information on Switch C.
<SwitchC> display bfd session verbose
Total Session Num: 1 Up Session Num: 1 Init Mode: Active
IPv6 Session Working Under Ctrl Mode:
Local Discr: 513 Remote Discr: 513
Source IP: 3001::3
Destination IP: 3000::1
Session State: Up Interface: N/A
Min Tx Inter: 500ms Act Tx Inter: 500ms
Min Rx Inter: 500ms Detect Inter: 2500ms
Rx Count: 13 Tx Count: 14
Connect Type: Indirect Running Up for: 00:00:05
Hold Time: 2243ms Auth mode: None
Detect Mode: Async Slot: 0
Protocol: BGP4+
Version:1
Diag Info: No Diagnostic
The output shows that a BFD session has been established between Switch A and Switch C.
# Display BGP peer information on Switch C.
<SwitchC> display bgp peer ipv6
BGP local router ID: 3.3.3.3
Local AS number: 200
Total number of peers: 2 Peers in established state: 2
* - Dynamically created peer
Peer AS MsgRcvd MsgSent OutQ PrefRcv Up/Down State
2000::1 200 8 8 0 0 00:04:45 Established
3000::1 200 5 4 0 0 00:01:53 Established
The output shows that Switch C has established two BGP connections with Switch A, and both connections are in Established state.
# Display route 1200::0/64 on Switch C.
<SwitchC> display ipv6 routing-table 1200::0 64 verbose
Summary count : 1
Destination: 1200::/64
Protocol: BGP4+ Process ID: 0
SubProtID: 0x1 Age: 00h01m07s
Cost: 50 Preference: 255
IpPre: N/A QosLocalID: N/A
Tag: 0 State: Active Adv
OrigTblID: 0x1 OrigVrf: default-vrf
TableID: 0xa OrigAs: 0
NibID: 0x25000001 LastAs: 0
AttrID: 0x1 Neighbor: 3000::1
Flags: 0x10060 OrigNextHop: 3000::1
Label: NULL RealNextHop: FE80::20C:29FF:FE4A:3873
BkLabel: NULL BkNextHop: N/A
Tunnel ID: Invalid Interface: Vlan-interface101
BkTunnel ID: Invalid BkInterface: N/A
The output shows that Switch C communicates with network 1200::0/64 through the path Switch C<—>Switch B<—>Switch A.
# Break down the path Switch C<—>Switch B<—>Switch A and then display route 1200::0/64 on Switch C.
<SwitchC> display ipv6 routing-table 1200::0 64 verbose
Summary count : 1
Destination: 1200::/64
Protocol: BGP4+ Process ID: 0
SubProtID: 0x1 Age: 00h00m57s
Cost: 100 Preference: 255
IpPre: N/A QosLocalID: N/A
Tag: 0 State: Active Adv
OrigTblID: 0x1 OrigVrf: default-vrf
TableID: 0xa OrigAs: 0
NibID: 0x25000000 LastAs: 0
AttrID: 0x0 Neighbor: 2000::1
Flags: 0x10060 OrigNextHop: 2000::1
Label: NULL RealNextHop: FE80::20C:29FF:FE40:715
BkLabel: NULL BkNextHop: N/A
Tunnel ID: Invalid Interface: Vlan-interface201
BkTunnel ID: Invalid BkInterface: N/A
The output shows that Switch C communicates with network 1200::0/64 through the path Switch C<—>Switch D<—>Switch A.
IPv6 BGP FRR configuration example
Network requirements
As shown in Figure 83, configure BGP FRR so that when Link B fails, BGP uses Link A to forward traffic.
Configuration procedure
1. Configure IPv6 addresses for interfaces. (Details not shown.)
2. Configure OSPFv3 in AS 200 to ensure connectivity among Switch B, Switch C, and Switch D. (Details not shown.)
3. Configure BGP connections:
# Configure Switch A to establish EBGP sessions to Switch B and Switch C, and advertise network 1::/64.
<SwitchA> system-view
[SwitchA] bgp 100
[SwitchA] router-id 1.1.1.1
[SwitchA-bgp-default] peer 3001::2 as-number 200
[SwitchA-bgp-default] peer 2001::2 as-number 200
[SwitchA-bgp-default] address-family ipv6 unicast
[SwitchA-bgp-default-ipv6] peer 3001::2 enable
[SwitchA-bgp-default-ipv6] peer 2001::2 enable
[SwitchA-bgp-default-ipv6] network 1:: 64
[SwitchA-bgp-default-ipv6] quit
[SwitchA-bgp-default] quit
# Configure Switch B to establish an EBGP session to Switch A, and an IBGP session to Switch D.
<SwitchB> system-view
[SwitchB] bgp 200
[SwitchB] router-id 2.2.2.2
[SwitchB-bgp-default] peer 3001::1 as-number 100
[SwitchB-bgp-default] peer 3002::2 as-number 200
[SwitchB-bgp-default] address-family ipv6 unicast
[SwitchB-bgp-default-ipv6] peer 3001::1 enable
[SwitchB-bgp-default-ipv6] peer 3002::2 enable
[SwitchB-bgp-default-ipv6] peer 3002::2 next-hop-local
[SwitchB-bgp-default-ipv6] quit
[SwitchB-bgp-default] quit
# Configure Switch C to establish an EBGP session to Switch A, and an IBGP session to Switch D.
<SwitchC> system-view
[SwitchC] bgp 200
[SwitchC] router-id 3.3.3.3
[SwitchC-bgp-default] peer 2001::1 as-number 100
[SwitchC-bgp-default] peer 2002::2 as-number 200
[SwitchC-bgp-default] address-family ipv6 unicast
[SwitchC-bgp-default-ipv6] peer 2001::1 enable
[SwitchC-bgp-default-ipv6] peer 2002::2 enable
[SwitchC-bgp-default-ipv6] peer 2002::2 next-hop-local
[SwitchC-bgp-default-ipv6] quit
[SwitchC-bgp-default] quit
# Configure Switch D to establish IBGP sessions to Switch B and Switch C, and advertise network 4::/64.
<SwitchD> system-view
[SwitchD] bgp 200
[SwitchD-bgp-default] peer 3002::1 as-number 200
[SwitchD-bgp-default] peer 2002::1 as-number 200
[SwitchD-bgp-default] address-family ipv6 unicast
[SwitchD-bgp-default-ipv6] peer 3002::1 enable
[SwitchD-bgp-default-ipv6] peer 2002::1 enable
[SwitchD-bgp-default-ipv6] network 4:: 64
[SwitchD-bgp-default-ipv6] quit
[SwitchD-bgp-default] quit
4. Configure preferred values so Link B is used to forward traffic between Switch A and Switch D:
# Configure Switch A to set the preferred value to 100 for routes received from Switch B.
[SwitchA-bgp-default-ipv6] peer 3001::2 preferred-value 100
[SwitchA-bgp-default-ipv6] quit
[SwitchA-bgp-default] quit
# Configure Switch D to set the preferred value to 100 for routes received from Switch B.
[SwitchD-bgp-default-ipv6] peer 3002::1 preferred-value 100
[SwitchD-bgp-default-ipv6] quit
[SwitchD-bgp-default] quit
5. Configure BGP FRR:
# On Switch A, create routing policy frr to set a backup next hop 2001::2 (Switch C) for the route destined for 4::/64.
<SwitchA> system-view
[SwitchA] ipv6 prefix-list abc index 10 permit 4:: 64
[SwitchA] route-policy frr permit node 10
[SwitchA-route-policy] if-match ipv6 address prefix-list abc
[SwitchA-route-policy] apply ipv6 fast-reroute backup-nexthop 2001::2
[SwitchA-route-policy] quit
# Apply the routing policy to BGP FRR for BGP IPv6 unicast address family.
[SwitchA] bgp 100
[SwitchA-bgp-default] address-family ipv6 unicast
[SwitchA-bgp-default-ipv6] fast-reroute route-policy frr
[SwitchA-bgp-default-ipv6] quit
[SwitchA-bgp-default] quit
# On Switch D, create routing policy frr to set a backup next hop 2002::1 (Switch C) for the route destined for 1::/64.
<SwitchD> system-view
[SwitchD] ipv6 prefix-list abc index 10 permit 1:: 64
[SwitchD] route-policy frr permit node 10
[SwitchD-route-policy] if-match ipv6 address prefix-list abc
[SwitchD-route-policy] apply ipv6 fast-reroute backup-nexthop 2002::1
[SwitchD-route-policy] quit
# Apply the routing policy to BGP FRR for BGP IPv6 unicast address family.
[SwitchD] bgp 200
[SwitchD-bgp-default] address-family ipv6 unicast
[SwitchD-bgp-default-ipv6] fast-reroute route-policy frr
[SwitchD-bgp-default-ipv6] quit
[SwitchD-bgp-default] quit
Verifying the configuration
# Display detailed information about the route to 4::/64 on Switch A. The output shows the backup next hop for the route.
[SwitchA] display ipv6 routing-table 4:: 64 verbose
Summary count : 1
Destination: 4::/64
Protocol: BGP4+ Process ID: 0
SubProtID: 0x2 Age: 00h00m58s
Cost: 0 Preference: 255
IpPre: N/A QosLocalID: N/A
Tag: 0 State: Active Adv
OrigTblID: 0x0 OrigVrf: default-vrf
TableID: 0xa OrigAs: 200
NibID: 0x25000003 LastAs: 200
AttrID: 0x3 Neighbor: 3001::2
Flags: 0x10060 OrigNextHop: 3001::2
Label: NULL RealNextHop: 3001::2
BkLabel: NULL BkNextHop: 2001::2
Tunnel ID: Invalid Interface: Vlan-interface 100
BkTunnel ID: Invalid BkInterface: Vlan-interface 200
FtnIndex: 0x0
# Display detailed information about the route to 1::/64 on Switch D. The output shows the backup next hop for the route.
[SwitchD] display ipv6 routing-table 1:: 64 verbose
Summary count : 1
Destination: 1::/64
Protocol: BGP4+ Process ID: 0
SubProtID: 0x1 Age: 00h03m24s
Cost: 0 Preference: 255
IpPre: N/A QosLocalID: N/A
Tag: 0 State: Active Adv
OrigTblID: 0x0 OrigVrf: default-vrf
TableID: 0xa OrigAs: 100
NibID: 0x25000003 LastAs: 100
AttrID: 0x4 Neighbor: 3002::1
Flags: 0x10060 OrigNextHop: 3002::1
Label: NULL RealNextHop: 3002::1
BkLabel: NULL BkNextHop: 2002::1
Tunnel ID: Invalid Interface: Vlan-interface 101
BkTunnel ID: Invalid BkInterface: Vlan-interface 201
FtnIndex: 0x0
Troubleshooting BGP
Symptom
The display bgp peer ipv4 unicast or display bgp peer ipv6 unicast command output shows that the state of the connection to a peer cannot become established.
Analysis
To become BGP peers, any two routers must establish a TCP connection using port 179 and exchange Open messages successfully.
Solution
1. To resolve the problem:
a. Use the display current-configuration command to verify the current configuration, and verify that the peer's AS number is correct.
b. Use the display bgp peer ipv4 unicast or display bgp peer ipv6 unicast command to verify that the peer's IP/IPv6 address is correct.
c. If a loopback interface is used, verify that the loopback interface is specified with the peer connect-interface command.
d. If the peer is a non-direct EBGP peer, verify that the peer ebgp-max-hop command is configured.
e. If the peer ttl-security hops command is configured, verify that the command is configured on the peer. Verify that the hop-count values configured on them are greater than the number of hops between them.
f. Verify that a valid route to the peer is available.
g. Use the ping command to verify the connectivity to the peer.
h. Use the display tcp verbose or display ipv6 tcp verbose command to verify the TCP connection.
i. Verify that no ACL rule is applied to disable TCP port 179.
2. If the problem persists, contact H3C Support.
Configuring PBR
Overview
Policy-based routing (PBR) uses user-defined policies to route packets. A policy can specify the next hop, default next hop, and precedence for packets that match specific criteria such as ACLs.
The device forwards received packets using the following process:
1. The device uses PBR to forward matching packets.
2. If the packets do not match the PBR policy or the PBR-based forwarding fails, the device uses the routing table, excluding the default route, to forward the packets.
3. If the routing table-based forwarding fails, the device uses the default next hop defined in PBR to forward packets.
4. If the default next hop or default output interface-based forwarding fails, the device uses the default route to forward packets.
PBR includes the following types:
· Local PBR—Guides the forwarding of locally generated packets, such as ICMP packets generated by using the ping command.
· Interface PBR—Guides the forwarding of packets received on an interface.
· Outbound PBR on a VXLAN tunnel interface—Guides the forwarding of outgoing packets when equal-cost routes exist.
Policy
A policy includes match criteria and actions to be taken on the matching packets. A policy can have one or multiple nodes as follows:
· Each node is identified by a node number. A smaller node number has a higher priority.
· A node contains if-match and apply clauses. An if-match clause specifies a match criterion, and an apply clause specifies an action.
· A node has a match mode of permit or deny.
A policy compares packets with nodes in priority order. If a packet matches the criteria on a node, it is processed by the action on the node. Otherwise, it goes to the next node for a match. If the packet does not match the criteria on any node, it is forwarded according to the routing table.
if-match clause
PBR supports the following types of if-match clauses:
· if-match acl—Sets an ACL match criterion.
· if-match vxlan-id—Sets the VXLAN match criterion. For more information about VXLAN, see VXLAN Configuration Guide.
On a node, you can specify multiple types of if-match clauses. To match a node, a packet must match all types of the if-match clauses for the node but only one if-match clause for each type.
apply clause
PBR supports the types of apply clauses shown in Table 22. You can specify multiple apply clauses for a node, but some of them might not be executed.
Table 22 Priorities and meanings of apply clauses
Clause |
Meaning |
Priority |
apply precedence |
Sets an IP precedence. |
This clause is always executed. |
apply next-hop |
Sets next hops. |
This clause is always executed. |
apply default-next-hop |
Sets default next hops. |
This clause takes effect only when no next hop is set or the next hop is invalid, and the packet does not match any route in the routing table. |
Relationship between the match mode and clauses on the node
Does a packet match all the if-match clauses on the node? |
Match mode |
|
Permit |
Deny |
|
Yes. |
· If the node is configured with apply clauses, PBR executes the apply clauses on the node. If the PBR-based forwarding succeeds, PBR does not compare the packet with the next node. · If the node is configured with no apply clauses, the packet is forwarded according to the routing table. |
The packet is forwarded according to the routing table. |
No. |
PBR compares the packet with the next node. |
PBR compares the packet with the next node. |
A node that has no if-match clauses matches any packet.
PBR and Track
PBR can work with the Track feature to dynamically adapt the availability status of an apply clause to the link status of a tracked object. The tracked object can be a next hop or default next hop.
· When the track entry associated with an object changes to Negative, the apply clause is invalid.
· When the track entry changes to Positive or NotReady, the apply clause is valid.
For more information about Track-PBR collaboration, see High Availability Configuration Guide.
Restrictions and guidelines: PBR configuration
PBR configuration task list
Tasks at a glance |
(Required.) Configuring a policy: |
(Required.) Specifying a policy for PBR · Specifying a policy for local PBR · Specifying a policy for interface PBR · Specifying a policy for outbound PBR on a VXLAN tunnel interface |
Configuring a policy
Creating a node
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Create a node for a policy, and enter its view. |
policy-based-route policy-name [ deny | permit ] node node-number |
By default, no policy nodes exist. |
Setting match criteria for a node
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter policy node view. |
policy-based-route policy-name [ deny | permit ] node node-number |
N/A |
3. Set an ACL match criterion. |
if-match acl { acl-number | name acl-name } |
By default, no ACL match criterion is set. The ACL match criterion cannot match Layer 2 information. If a policy is applied to a VSI interface, the ACL match criterion in the policy can match only the inner IP addresses in VXLAN packets. |
4. Set a VXLAN match criterion. |
if-match vxlan-id vxlan-id |
By default, no VXLAN match criterion is set. This command is applicable to VXLAN networks. When equal-cost routes exist, you can configure this match criterion to select a route for packets based on VXLAN IDs. On a transport network device, you can configure PBR on the Layer 3 interface to guide the forwarding of packets based on VXLAN IDs. On a VTEP, you can configure PBR on the tunnel interface to guide the forwarding of packets based on VXLAN IDs. |
|
NOTE: If an ACL match criterion is defined, packets are compared with the ACL rule. The permit or deny action and the time range of the specified ACL are ignored. If the specified ACL does not exist, no packet is matched. |
Configuring actions for a node
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter policy node view. |
policy-based-route policy-name [ deny | permit ] node node-number |
N/A |
3. Set an IP precedence. |
apply precedence { type | value } |
By default, no IP precedence is specified. |
4. Set next hops. |
apply next-hop [ vpn-instance vpn-instance-name ] { ip-address [ direct ] [ track track-entry-number ] }&<1-n> |
By default, no next hop is specified. You can specify multiple next hops for backup in one command line or by executing this command multiple times. You can specify a maximum of two next hops for a node. For outbound PBR on a VXLAN tunnel interface, you can specify only one next hop and the next hop must be directly connected. |
5. Set default next hops. |
apply default-next-hop [ vpn-instance vpn-instance-name ] { ip-address [ direct ] [ track track-entry-number ] }&<1-n> |
By default, no default next hop is specified. You can specify multiple default next hops for backup in one command line or by executing this command multiple times. You can specify a maximum of two default next hops for a node. |
Specifying a policy for PBR
Support for local PBR, interface PBR, and outbound PBR on a VXLAN tunnel interface depends on the VXLAN hardware resource allocation mode.
· If the normal mode is specified, the interface module supports local PBR and interface PBR.
· If the MAC address mode is specified, the interface module supports local PBR, interface PBR, and outbound PBR on a VXLAN tunnel interface.
You can use the hardware-resource vxlan command to set the VXLAN hardware resource allocation mode.
Specifying a policy for local PBR
Local PBR might affect local services, such as ping and Telnet. When you use local PBR, make sure you fully understand its impact on local services of the device.
You can specify only one policy for local PBR and must make sure the specified policy already exists.
Before you apply a new policy, you must first remove the current policy.
To specify a policy for local PBR:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Specify a policy for local PBR. |
ip local policy-based-route policy-name |
By default, local PBR is not enabled. |
Specifying a policy for interface PBR
You can specify only one policy for interface PBR and must make sure the specified policy already exists.
Before you can apply a new policy to an interface, you must first remove the current policy from the interface.
You can apply a policy to multiple interfaces.
To specify a policy for interface PBR on an interface:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Specify a policy for interface PBR. |
ip policy-based-route policy-name |
By default, no interface policy is applied to an interface. |
4. Quit interface view. |
quit |
N/A |
5. (Optional.) Specify a policy for a list of VLAN interfaces. |
ip policy-based-route policy-name apply vlan-interface interface-list |
By default, no policy is applied to the specified VLAN interfaces. When you want to specify a policy for multiple VLAN interfaces on a device, use this command to simplify configuration and save device resources. |
Specifying a policy for outbound PBR on a VXLAN tunnel interface
In a VXLAN network, equal-cost routes might exist between two endpoints of a VXLAN tunnel. The device cannot route VXLAN packets to the exact next hop. To choose the desired next hop for outgoing VXLAN packets, use outbound PBR on the VXLAN tunnel interface.
The outbound PBR configuration takes effect only on VXLAN IP gateways.
You can specify only one policy for interface PBR and must make sure the specified policy already exists.
Before you can apply a new policy to an interface, you must first remove the current policy from the interface.
To specify a policy for outbound PBR on a VXLAN tunnel interface:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Create a VXLAN tunnel interface and enter tunnel interface view. |
interface tunnel tunnel-number mode vxlan |
By default, no tunnel interfaces exist. The endpoints of a tunnel must use the same tunnel mode to correctly transmit packets. |
3. Specify a policy for outbound PBR. |
ip policy-based-route policy-name egress |
By default, no policy is specified for outbound PBR on a VXLAN tunnel interface. |
Displaying and maintaining PBR
Execute display commands in any view and reset commands in user view.
Task |
Command |
Display PBR policy information. |
display ip policy-based-route [ policy policy-name ] |
(In standalone mode.) Display the PBR configuration and statistics for a VLAN interface. |
display ip policy-based-route apply vlan-interface interface-number [ slot slot-number ] |
(In IRF mode.) Display the PBR configuration and statistics for a VLAN interface. |
display ip policy-based-route apply vlan-interface interface-number [ chassis chassis-number slot slot-number ] |
Display PBR configuration. |
display ip policy-based-route setup |
(In standalone mode.) Display the outbound PBR configuration and statistics for a VXLAN tunnel interface. |
display ip policy-based-route egress interface interface-type interface-number [ slot slot-number ] |
(In IRF mode.) Display the outbound PBR configuration and statistics for a VXLAN tunnel interface. |
display ip policy-based-route egress interface interface-type interface-number [ chassis chassis-number slot slot-number ] |
(In standalone mode.) Display local PBR configuration and statistics. |
display ip policy-based-route local [ slot slot-number ] |
(In IRF mode.) Display local PBR configuration and statistics. |
display ip policy-based-route local [ chassis chassis-number slot slot-number ] |
(In standalone mode.) Display interface PBR configuration and statistics. |
display ip policy-based-route interface interface-type interface-number [ slot slot-number ] |
(In IRF mode.) Display interface PBR configuration and statistics. |
display ip policy-based-route interface interface-type interface-number [ chassis chassis-number slot slot-number ] |
Clear PBR statistics. |
reset ip policy-based-route statistics [ policy policy-name ] |
PBR configuration examples
Packet type-based local PBR configuration example
Network requirements
As shown in Figure 84, Switch B and Switch C cannot reach each other.
Configure PBR on Switch A to forward all TCP packets to the next hop 1.1.2.2 (Switch B).
Configuration procedure
1. Configure Switch A:
# Create VLAN 10 and VLAN 20.
<SwitchA> system-view
[SwitchA] vlan 10
[SwitchA-vlan10] quit
[SwitchA] vlan 20
[SwitchA-vlan20] quit
# Configure the IP addresses of VLAN-interface 10 and VLAN-interface 20.
[SwitchA] interface vlan-interface 10
[SwitchA-Vlan-interface10] ip address 1.1.2.1 24
[SwitchA-Vlan-interface10] quit
[SwitchA] interface vlan-interface 20
[SwitchA-Vlan-interface20] ip address 1.1.3.1 24
[SwitchA-Vlan-interface20] quit
# Configure ACL 3101 to match TCP packets.
[SwitchA] acl advanced 3101
[SwitchA-acl-ipv4-adv-3101] rule permit tcp
[SwitchA-acl-ipv4-adv-3101] quit
# Configure Node 5 for the policy aaa to forward TCP packets to next hop 1.1.2.2.
[SwitchA] policy-based-route aaa permit node 5
[SwitchA-pbr-aaa-5] if-match acl 3101
[SwitchA-pbr-aaa-5] apply next-hop 1.1.2.2
[SwitchA-pbr-aaa-5] quit
# Configure local PBR by applying the policy aaa to Switch A.
[SwitchA] ip local policy-based-route aaa
2. Configure Switch B:
# Create VLAN 10.
<SwitchB> system-view
[SwitchB] vlan 10
[SwitchB-vlan10] quit
# Configure the IP address of VLAN-interface 10.
[SwitchB] interface vlan-interface 10
[SwitchB-Vlan-interface10] ip address 1.1.2.2 24
3. Configure Switch C:
# Create VLAN 20.
<SwitchC> system-view
[SwitchC] vlan 20
[SwitchC-vlan20] quit
# Configure the IP address of VLAN-interface 20.
[SwitchC] interface vlan-interface 20
[SwitchC-Vlan-interface20] ip address 1.1.3.2 24
Verifying the configuration
# Telnet to Switch B on Switch A. The operation succeeds. (Details not shown.)
# Telnet to Switch C on Switch A. The operation fails. (Details not shown.)
# Ping Switch C from Switch A. The operation succeeds. (Details not shown.)
Telnet uses TCP, and ping uses ICMP. The results show the following:
· All TCP packets sent from Switch A are forwarded to the next hop 1.1.2.2.
· Other packets are forwarded through VLAN-interface 20.
· The local PBR configuration is effective.
Packet type-based interface PBR configuration example
Network requirements
As shown in Figure 85, Switch B and Switch C cannot reach each other.
Configure PBR on Switch A to forward all TCP packets received on VLAN-interface 11 to the next hop 1.1.2.2 (Switch B).
Configuration procedure
1. Make sure Switch B and Switch C can reach Host A. (Details not shown.)
2. Configure Switch A:
# Create VLAN 10 and VLAN 20.
<SwitchA> system-view
[SwitchA] vlan 10
[SwitchA-vlan10] quit
[SwitchA] vlan 20
[SwitchA-vlan20] quit
# Configure the IP addresses of VLAN-interface 10 and VLAN-interface 20.
[SwitchA] interface vlan-interface 10
[SwitchA-Vlan-interface10] ip address 1.1.2.1 24
[SwitchA-Vlan-interface10] quit
[SwitchA] interface vlan-interface 20
[SwitchA-Vlan-interface20] ip address 1.1.3.1 24
[SwitchA-Vlan-interface20] quit
# Configure ACL 3101 to match TCP packets.
[SwitchA] acl advanced 3101
[SwitchA-acl-ipv4-adv-3101] rule permit tcp
[SwitchA-acl-ipv4-adv-3101] quit
# Configure Node 5 for the policy aaa to forward TCP packets to next hop 1.1.2.2.
[SwitchA] policy-based-route aaa permit node 5
[SwitchA-pbr-aaa-5] if-match acl 3101
[SwitchA-pbr-aaa-5] apply next-hop 1.1.2.2
[SwitchA-pbr-aaa-5] quit
# Configure interface PBR by applying the policy aaa to VLAN-interface 11.
[SwitchA] interface vlan-interface 11
[SwitchA-Vlan-interface11] ip address 10.110.0.10 24
[SwitchA-Vlan-interface11] ip policy-based-route aaa
[SwitchA-Vlan-interface11] quit
Verifying the configuration
# On Host A, Telnet to Switch B that is directly connected to Switch A. The operation succeeds. (Details not shown.)
# On Host A, Telnet to Switch C that is directly connected to Switch A. The operation fails. (Details not shown.)
# Ping Switch C from Host A. The operation succeeds. (Details not shown.)
Telnet uses TCP, and ping uses ICMP. The results show the following:
· All TCP packets arriving on VLAN-interface 11 of Switch A are forwarded to next hop 1.1.2.2.
· Other packets are forwarded through VLAN-interface 20.
· The interface PBR configuration is effective.
Configuring IPv6 static routing
Static routes are manually configured and cannot adapt to network topology changes. If a fault or a topological change occurs in the network, the network administrator must modify the static routes manually. IPv6 static routing works well in a simple IPv6 network.
Configuring an IPv6 static route
Before you configure an IPv6 static route, complete the following tasks:
· Configure parameters for the related interfaces.
· Configure link layer attributes for the related interfaces.
· Make sure the neighboring nodes can reach each other.
To configure an IPv6 static route:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Configure an IPv6 static route. |
·
Method 1: ·
Method 2: |
By default, no IPv6 static route is configured. |
3. (Optional.) Set the default preference for IPv6 static routes. |
ipv6 route-static default-preference default-preference |
The default setting is 60. |
4. (Optional.) Delete all IPv6 static routes, including the default route. |
delete ipv6 [ vpn-instance vpn-instance-name ] static-routes all |
The undo ipv6 route-static command deletes one IPv6 static route. |
Configuring BFD for IPv6 static routes
BFD provides a general purpose, standard, and medium- and protocol-independent fast failure detection mechanism. It can uniformly and quickly detect the failures of the bidirectional forwarding paths between two routers for protocols, such as routing protocols and MPLS. For more information about BFD, see High Availability Configuration Guide.
|
IMPORTANT: Enabling BFD for a flapping route could worsen the situation. |
Bidirectional control mode
To use BFD bidirectional control detection between two devices, enable BFD control mode for each device's static route destined to the peer.
To configure a static route and enable BFD control mode, use one of the following methods:
· Specify an output interface and a direct next hop.
· Specify an indirect next hop and a BFD packet source address for the static route.
To configure BFD control mode for an IPv6 static route (direct next hop):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Configure BFD control mode for an IPv6 static route. |
ipv6 route-static [ vpn-instance s-vpn-instance-name ] ipv6-address prefix-length interface-type interface-number next-hop-address bfd control-packet [ bfd-source ipv6-address ] [ preference preference ] [ tag tag-value ] [ description text ] |
By default, BFD control mode for an IPv6 static route is not configured. |
To configure BFD control mode for an IPv6 static route (indirect next hop):
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Configure BFD control mode for an IPv6 static route. |
ipv6 route-static [ vpn-instance s-vpn-instance-name ] ipv6-address prefix-length [ vpn-instance d-vpn-instance-name ] { next-hop-address bfd control-packet bfd-source ipv6-address } [ preference preference ] [ tag tag-value ] [ description text ] |
By default, BFD control mode for an IPv6 static route is not configured. |
Single-hop echo mode
With BFD echo mode enabled for a static route, the output interface sends BFD echo packets to the destination device, which loops the packets back to test the link reachability.
|
IMPORTANT: Do not use BFD for a static route with the output interface in spoofing state. |
To configure BFD echo mode for an IPv6 static route:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Configure the source address of echo packets. |
bfd echo-source-ipv6 ipv6-address |
By default, the source address of echo packets is not configured. The source address of echo packets must be a global unicast address. For more information about this command, see High Availability Command Reference. |
3. Configure BFD echo mode for an IPv6 static route. |
ipv6 route-static [ vpn-instance s-vpn-instance-name ] ipv6-address prefix-length interface-type interface-number next-hop-address bfd echo-packet [ bfd-source ipv6-address ] [ preference preference ] [ tag tag-value ] [ description text ] |
By default, BFD echo mode for an IPv6 static route is not configured. The next hop IPv6 address must be a global unicast address. |
Displaying and maintaining IPv6 static routes
Execute display commands in any view.
Task |
Command |
Display IPv6 static route information. |
display ipv6 routing-table protocol static [ inactive | verbose ] |
Display IPv6 static route next hop information. |
display ipv6 route-static nib [ nib-id ] [ verbose ] |
Display IPv6 static routing table information. |
display ipv6 route-static routing-table [ vpn-instance vpn-instance-name ] [ ipv6-address prefix-length ] |
IPv6 static routing configuration examples
Basic IPv6 static route configuration example
Network requirements
As shown in Figure 86, configure IPv6 static routes so that hosts can reach one another.
Configuration procedure
1. Configure the IPv6 addresses for all VLAN interfaces. (Details not shown.)
2. Configure IPv6 static routes:
# Configure a default IPv6 static route on Switch A.
<SwitchA> system-view
[SwitchA] ipv6 route-static :: 0 4::2
# Configure two IPv6 static routes on Switch B.
<SwitchB> system-view
[SwitchB] ipv6 route-static 1:: 64 4::1
[SwitchB] ipv6 route-static 3:: 64 5::1
# Configure a default IPv6 static route on Switch C.
<SwitchC> system-view
[SwitchC] ipv6 route-static :: 0 5::2
3. Configure the IPv6 addresses for all the hosts and configure the default gateway of Host A, Host B, and Host C as 1::1, 2::1, and 3::1.
Verifying the configuration
# Display the IPv6 static route information on Switch A.
[SwitchA] display ipv6 routing-table protocol static
Summary Count : 1
Static Routing table Status : <Active>
Summary Count : 1
Destination: :: Protocol : Static
NextHop : 4::2 Preference: 60
Interface : Vlan-interface200 Cost : 0
Static Routing table Status : <Inactive>
Summary Count : 0
# Display the IPv6 static route information on Switch B.
[SwitchB] display ipv6 routing-table protocol static
Summary Count : 2
Static Routing table Status : <Active>
Summary Count : 2
Destination: 1::/64 Protocol : Static
NextHop : 4::1 Preference: 60
Interface : Vlan-interface200 Cost : 0
Destination: 3::/64 Protocol : Static
NextHop : 5::1 Preference: 60
Interface : Vlan-interface300 Cost : 0
Static Routing table Status : <Inactive>
Summary Count : 0
# Use the ping command to test the reachability.
[SwitchA] ping ipv6 3::1
Ping6(56 data bytes) 4::1 --> 3::1, press CTRL_C to break
56 bytes from 3::1, icmp_seq=0 hlim=62 time=0.700 ms
56 bytes from 3::1, icmp_seq=1 hlim=62 time=0.351 ms
56 bytes from 3::1, icmp_seq=2 hlim=62 time=0.338 ms
56 bytes from 3::1, icmp_seq=3 hlim=62 time=0.373 ms
56 bytes from 3::1, icmp_seq=4 hlim=62 time=0.316 ms
--- Ping6 statistics for 3::1 ---
5 packet(s) transmitted, 5 packet(s) received, 0.0% packet loss
round-trip min/avg/max/std-dev = 0.316/0.416/0.700/0.143 ms
BFD for IPv6 static routes configuration example (direct next hop)
Network requirements
As shown in Figure 87:
· Configure an IPv6 static route to subnet 120::/64 on Switch A.
· Configure an IPv6 static route to subnet 121::/64 on Switch B.
· Enable BFD for both routes.
· Configure an IPv6 static route to subnet 120::/64 and an IPv6 static route to subnet 121::/64 on Switch C.
When the link between Switch A and Switch B through the Layer 2 switch fails, BFD can detect the failure immediately, and Switch A and Switch B can communicate through Switch C.
Figure 87 Network diagram
Table 23 Interface and IP address assignment
Device |
Interface |
IPv6 address |
Switch A |
Vlan-int10 |
12::1/64 |
Switch A |
Vlan-int11 |
10::102/64 |
Switch B |
Vlan-int10 |
12::2/64 |
Switch B |
Vlan-int13 |
13::1/64 |
Switch C |
Vlan-int11 |
10::100/64 |
Switch C |
Vlan-int13 |
13::2/64 |
Configuration procedure
1. Configure IPv6 addresses for interfaces. (Details not shown.)
2. Configure IPv6 static routes and BFD:
# Configure IPv6 static routes on Switch A and enable BFD control mode for the static route that traverses the Layer 2 switch.
<SwitchA> system-view
[SwitchA] interface vlan-interface 10
[SwitchA-vlan-interface10] bfd min-transmit-interval 500
[SwitchA-vlan-interface10] bfd min-receive-interval 500
[SwitchA-vlan-interface10] bfd detect-multiplier 9
[SwitchA-vlan-interface10] quit
[SwitchA] ipv6 route-static 120:: 64 vlan-interface 10 12::2 bfd control-packet
[SwitchA] ipv6 route-static 120:: 64 10::100 preference 65
[SwitchA] quit
# Configure IPv6 static routes on Switch B and enable BFD control mode for the static route that traverses the Layer 2 switch.
<SwitchB> system-view
[SwitchB] interface vlan-interface 10
[SwitchB-vlan-interface10] bfd min-transmit-interval 500
[SwitchB-vlan-interface10] bfd min-receive-interval 500
[SwitchB-vlan-interface10] bfd detect-multiplier 9
[SwitchB-vlan-interface10] quit
[SwitchB] ipv6 route-static 121:: 64 vlan-interface 10 12::1 bfd control-packet
[SwitchB] ipv6 route-static 121:: 64 vlan-interface 13 13::2 preference 65
[SwitchB] quit
# Configure IPv6 static routes on Switch C.
<SwitchC> system-view
[SwitchC] ipv6 route-static 120:: 64 13::1
[SwitchC] ipv6 route-static 121:: 64 10::102
Verifying the configuration
# Display the BFD sessions on Switch A.
<SwitchA> display bfd session
Total Session Num: 1 Up Session Num: 1 Init Mode: Active
IPv6 Session Working Under Ctrl Mode:
Local Discr: 513 Remote Discr: 33
Source IP: 12::1
Destination IP: 12::2
Session State: Up Interface: Vlan10
Hold Time: 2012ms
The output shows that the BFD session has been created.
# Display IPv6 static routes on Switch A.
<SwitchA> display ipv6 routing-table protocol static
Summary Count : 1
Static Routing table Status : <Active>
Summary Count : 1
Destination: 120::/64 Protocol : Static
NextHop : 12::2 Preference: 60
Interface : Vlan10 Cost : 0
Direct Routing table Status : <Inactive>
Summary Count : 0
The output shows that Switch A communicates with Switch B through VLAN-interface 10. The link over VLAN-interface 10 fails.
# Display IPv6 static routes on Switch A again.
<SwitchA> display ipv6 routing-table protocol static
Summary Count : 1
Static Routing table Status : <Active>
Summary Count : 1
Destination: 120::/64 Protocol : Static
NextHop : 10::100 Preference: 65
Interface : Vlan11 Cost : 0
Static Routing table Status : < Inactive>
Summary Count : 0
The output shows that Switch A communicates with Switch B through VLAN-interface 11.
BFD for IPv6 static routes configuration example (indirect next hop)
Network requirements
As shown in Figure 88:
· Switch A has a route to interface Loopback 1 (2::9/128) on Switch B, and the output interface is VLAN-interface 10.
· Switch B has a route to interface Loopback 1 (1::9/128) on Switch A, and the output interface is VLAN-interface 12.
· Switch D has a route to 1::9/128, and the output interface is VLAN-interface 10. It also has a route to 2::9/128, and the output interface is VLAN-interface 12.
Configure the following:
· Configure an IPv6 static route to subnet 120::/64 on Switch A.
· Configure an IPv6 static route to subnet 121::/64 on Switch B.
· Enable BFD for both routes.
· Configure an IPv6 static route to subnet 120::/64 and an IPv6 static route to subnet 121::/64 on both Switch C and Switch D.
When the link between Switch A and Switch B through Switch D fails, BFD can detect the failure immediately and Switch A and Switch B can communicate through Switch C.
Table 24 Interface and IP address assignment
Device |
Interface |
IPv6 address |
Switch A |
Vlan-int10 |
12::1/64 |
Switch A |
Vlan-int11 |
10::102/64 |
Switch A |
Loop1 |
1::9/128 |
Switch B |
Vlan-int12 |
11::2/64 |
Switch B |
Vlan-int13 |
13::1/64 |
Switch B |
Loop1 |
2::9/128 |
Switch C |
Vlan-int11 |
10::100/64 |
Switch C |
Vlan-int13 |
13::2/64 |
Switch D |
Vlan-int10 |
12::2/64 |
Switch D |
Vlan-int12 |
11::1/64 |
Configuration procedure
1. Configure IPv6 addresses for interfaces. (Details not shown.)
2. Configure IPv6 static routes and BFD:
# Configure IPv6 static routes on Switch A and enable BFD control packet mode for the IPv6 static route that traverses Switch D.
<SwitchA> system-view
[SwitchA] bfd multi-hop min-transmit-interval 500
[SwitchA] bfd multi-hop min-receive-interval 500
[SwitchA] bfd multi-hop detect-multiplier 9
[SwitchA] ipv6 route-static 120:: 64 2::9 bfd control-packet bfd-source 1::9
[SwitchA] ipv6 route-static 120:: 64 10::100 preference 65
[SwitchA] ipv6 route-static 2::9 128 12::2
[SwitchA] quit
# Configure IPv6 static routes on Switch B and enable BFD control packet mode for the static route that traverses Switch D.
<SwitchB> system-view
[SwitchB] bfd multi-hop min-transmit-interval 500
[SwitchB] bfd multi-hop min-receive-interval 500
[SwitchB] bfd multi-hop detect-multiplier 9
[SwitchB] ipv6 route-static 121:: 64 1::9 bfd control-packet bfd-source 2::9
[SwitchB] ipv6 route-static 121:: 64 13::2 preference 65
[SwitchB] ipv6 route-static 1::9 128 11::1
[SwitchB] quit
# Configure IPv6 static routes on Switch C.
<SwitchC> system-view
[SwitchC] ipv6 route-static 120:: 64 13::1
[SwitchC] ipv6 route-static 121:: 64 10::102
# Configure IPv6 static routes on Switch D.
<SwitchD> system-view
[SwitchD] ipv6 route-static 120:: 64 11::2
[SwitchD] ipv6 route-static 121:: 64 12::1
[SwitchD] ipv6 route-static 2::9 128 11::2
[SwitchD] ipv6 route-static 1::9 128 12::1
Verifying the configuration
# Display the BFD sessions on Switch A.
<SwitchA> display bfd session
Total Session Num: 1 Up Session Num: 1 Init Mode: Active
IPv6 Session Working Under Ctrl Mode:
Local Discr: 513 Remote Discr: 33
Source IP: 1::9
Destination IP: 2::9
Session State: Up Interface: N/A
Hold Time: 2012ms
The output shows that the BFD session has been created.
# Display the IPv6 static routes on Switch A.
<SwitchA> display ipv6 routing-table protocol static
Summary Count : 1
Static Routing table Status : <Active>
Summary Count : 1
Destination: 120::/64 Protocol : Static
NextHop : 2::9 Preference: 60
Interface : Vlan10 Cost : 0
Static Routing table Status : <Inactive>
Summary Count : 0
The output shows that Switch A communicates Switch B through VLAN-interface 10. The link over VLAN-interface 10 fails.
# Display IPv6 static routes on Switch A again.
<SwitchA> display ipv6 routing-table protocol static
Summary Count : 1
Static Routing table Status : <Active>
Summary Count : 1
Destination: 120::/64 Protocol : Static
NextHop : 10::100 Preference: 65
Interface : Vlan11 Cost : 0
Static Routing table Status : <Inactive>
Summary Count : 0
The output shows that Switch A communicates with Switch B through VLAN-interface 11.
Configuring an IPv6 default route
A default IPv6 route is used to forward packets that match no entry in the routing table.
A default IPv6 route can be configured in either of the following ways:
· The network administrator can configure a default route with a destination prefix of ::/0. For more information, see "Configuring IPv6 static routing."
· Some dynamic routing protocols, such as OSPFv3, IPv6 IS-IS, and RIPng, can generate a default IPv6 route. For example, an upstream router running OSPFv3 can generate a default IPv6 route and advertise it to other routers. These routers install the default IPv6 route with the next hop being the upstream router. For more information, see the respective chapters on those routing protocols in this configuration guide.
Configuring RIPng
Overview
RIP next generation (RIPng) is an extension of RIP-2 for support of IPv6. Most RIP concepts are applicable to RIPng.
RIPng is a distance vector routing protocol. It employs UDP to exchange route information through port 521. RIPng uses a hop count to measure the distance to a destination. The hop count is the metric or cost. The hop count from a router to a directly connected network is 0. The hop count between two directly connected routers is 1. When the hop count is greater than or equal to 16, the destination network or host is unreachable.
By default, the routing update is sent every 30 seconds. If the router receives no routing updates from a neighbor within 180 seconds, the routes learned from the neighbor are considered unreachable. If no routing update is received within another 240 seconds, the router removes these routes from the routing table.
RIPng for IPv6 has the following differences from RIP:
· UDP port number—RIPng uses UDP port 521 to send and receive routing information.
· Multicast address—RIPng uses FF02::9 as the link-local-router multicast address.
· Destination Prefix—128-bit destination address prefix.
· Next hop—128-bit IPv6 address.
· Source address—RIPng uses FE80::/10 as the link-local source address.
RIPng route entries
RIPng stores route entries in a database. Each route entry contains the following elements:
· Destination address—IPv6 address of a destination host or a network.
· Next hop address—IPv6 address of the next hop.
· Egress interface—Egress interface of the route.
· Metric—Cost from the local router to the destination.
· Route time—Time elapsed since the most recent update. The time is reset to 0 every time the route entry is updated.
· Route tag—Used for route control. For more information, see "Configuring routing policies."
RIPng packets
RIPng uses request and response packets to exchange routing information as follows:
1. When RIPng starts or needs to update some route entries, it sends a multicast request packet to neighbors.
2. When a RIPng neighbor receives the request packet, it sends back a response packet that contains the local routing table. RIPng can also advertise route updates in response packets periodically or advertise a triggered update caused by a route change.
3. After RIPng receives the response, it checks the validity of the response before adding routes to its routing table, including the following details:
? Whether the source IPv6 address is the link-local address.
? Whether the port number is correct.
4. A response packet that fails the check is discarded.
Protocols and standards
· RFC 2080, RIPng for IPv6
· RFC 2081, RIPng Protocol Applicability Statement
RIPng configuration task list
Tasks at a glance |
(Required.) Configuring basic RIPng |
(Optional.) Configuring RIPng route control: · Configuring an additional routing metric · Configuring RIPng route summarization · Configuring received/redistributed route filtering |
(Optional.) Tuning and optimizing the RIPng network: · Configuring split horizon and poison reverse · Configuring zero field check on RIPng packets · Setting the maximum number of ECMP routes |
(Optional.) Configuring RIPng GR |
(Optional.) Configuring RIPng NSR |
(Optional.) Configuring RIPng FRR |
Configuring basic RIPng
Before you configure basic RIPng, configure IPv6 addresses for interfaces to ensure IPv6 connectivity between neighboring nodes.
To configure basic RIPng:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enable RIPng and enter its view. |
ripng [ process-id ] [ vpn-instance vpn-instance-name ] |
By default, RIPng is disabled. |
3. Return to system view. |
quit |
N/A |
4. Enter interface view. |
interface interface-type interface-number |
N/A |
5. Enable RIPng on the interface. |
ripng process-id enable |
By default, RIPng is disabled. If RIPng is not enabled on an interface, the interface does not send or receive any RIPng route. |
Configuring RIPng route control
Before you configure RIPng, complete the following tasks:
· Configure IPv6 addresses for interfaces to ensure IPv6 connectivity between neighboring nodes.
· Configure basic RIPng.
Configuring an additional routing metric
An additional routing metric (hop count) can be added to the metric of an inbound or outbound RIPng route.
An outbound additional metric is added to the metric of a sent route, and it does not change the route's metric in the routing table.
An inbound additional metric is added to the metric of a received route before the route is added into the routing table, and the route's metric is changed.
To configure an inbound or outbound additional routing metric:
Command |
Remarks |
|
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Specify an inbound additional routing metric. |
ripng metricin value |
The default setting is 0. |
4. Specify an outbound additional routing metric. |
ripng metricout value |
The default setting is 1. |
Configuring RIPng route summarization
Configure route summarization on an interface, so RIPng advertises a summary route based on the longest match.
RIPng route summarization improves network scalability, reduces routing table size, and increases routing table lookup efficiency.
RIPng advertises a summary route with the smallest metric of all the specific routes.
For example, RIPng has two specific routes to be advertised through an interface: 1:11:11::24 with a metric of a 2 and 1:11:12::34 with a metric of 3. Configure route summarization on the interface, so RIPng advertises a single route 11::0/16 with a metric of 2.
To configure RIPng route summarization:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Advertise a summary IPv6 prefix. |
ripng summary-address ipv6-address prefix-length |
By default, the summary IPv6 prefix is not configured. |
Advertising a default route
You can configure RIPng to advertise a default route with the specified cost to its neighbors.
To configure RIPng to advertise a default route:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Configure RIPng to advertise a default route. |
ripng default-route { only | originate } [ cost cost-value | route-policy route-policy-name ] * |
By default, RIPng does not advertise a default route. This command advertises a default route on the current interface regardless of whether the default route exists in the local IPv6 routing table. |
Configuring received/redistributed route filtering
Perform this task to filter received or redistributed routes by using an IPv6 ACL or IPv6 prefix list. You can also configure RIPng to filter routes redistributed from other routing protocols and routes from a specified neighbor.
To configure a RIPng route filtering policy:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIPng view. |
ripng [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Configure a filter policy to filter received routes. |
filter-policy { ipv6-acl-number | prefix-list prefix-list-name } import |
By default, RIPng does not filter received routes. |
4. Configure a filter policy to filter redistributed routes. |
filter-policy { ipv6-acl-number | prefix-list prefix-list-name } export [ protocol [ process-id ] ] |
By default, RIPng does not filter redistributed routes. |
Setting a preference for RIPng
Routing protocols each have a preference. When they find routes to the same destination, the route found by the routing protocol with the highest preference is selected as the optimal route. You can manually set a preference for RIPng. The smaller the value, the higher the preference.
To set a preference for RIPng:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIPng view. |
ripng [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Set a preference for RIPng. |
preference { preference | route-policy route-policy-name } * |
By default, the preference of RIPng is 100. |
Configuring RIPng route redistribution
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIPng view. |
ripng [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Redistribute routes from other routing protocols. |
import-route protocol [ as-number | process-id ] [ allow-ibgp ] [ allow-direct | cost cost-value | route-policy route-policy-name ] * |
By default, RIPng does not redistribute routes from other routing protocols. |
4. (Optional.) Set a default routing metric for redistributed routes. |
default cost cost-value |
The default metric of redistributed routes is 0. |
Tuning and optimizing the RIPng network
This section describes how to tune and optimize the performance of the RIPng network as well as applications under special network environments.
Before you tune and optimize the RIPng network, complete the following tasks:
· Configure IPv6 addresses for interfaces to ensure IPv6 connectivity between neighboring nodes.
· Configure basic RIPng.
Setting RIPng timers
You can adjust RIPng timers to optimize the performance of the RIPng network.
When you adjust RIPng timers, consider the network performance, and perform unified configurations on routers running RIPng to avoid unnecessary network traffic or route oscillation.
To set RIPng timers:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIPng view. |
ripng [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Set RIPng timers. |
timers { garbage-collect garbage-collect-value | suppress suppress-value | timeout timeout-value | update update-value } * |
By default: · The update timer is 30 seconds. · The timeout timer is 180 seconds. · The suppress timer is 120 seconds. · The garbage-collect timer is 120 seconds. |
Configuring split horizon and poison reverse
If both split horizon and poison reverse are configured, only the poison reverse function takes effect.
Configuring split horizon
Split horizon disables RIPng from sending routes through the interface where the routes were learned to prevent routing loops between neighbors.
As a best practice, enable split horizon to prevent routing loops in normal cases.
To configure split horizon:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Enable split horizon. |
ripng split-horizon |
By default, split horizon is enabled. |
Configuring poison reverse
Poison reverse enables a route learned from an interface to be advertised through the interface. However, the metric of the route is set to 16, which means the route is unreachable.
To configure poison reverse:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Enable poison reverse. |
ripng poison-reverse |
By default, poison reverse is disabled. |
Configuring zero field check on RIPng packets
Some fields in the RIPng packet header must be zero. These fields are called zero fields. You can enable zero field check on incoming RIPng packets. If a zero field of a packet contains a non-zero value, RIPng does not process the packets. If you are certain that all packets are trustworthy, disable the zero field check to save CPU resources.
To configure RIPng zero field check:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIPng view. |
ripng [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Enable the zero field check on incoming RIPng packets. |
checkzero |
By default, zero field check is enabled for incoming RIPng packets. |
Setting the maximum number of ECMP routes
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIPng view. |
ripng [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Set the maximum number of ECMP routes. |
maximum load-balancing number |
By default, the maximum number of ECMP routes equals the maximum number of ECMP routes supported by the system. |
Configuring the RIPng packet sending rate
Perform this task to specify the interval for sending RIPng packets and the maximum number of RIPng packets that can be sent at each interval. This feature can avoid excessive RIPng packets from affecting system performance and consuming too much bandwidth.
To configure the RIPng packet sending rate:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIPng view. |
ripng [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Set the interval for sending RIPng packets and the maximum number of RIPng packets that can be sent at each interval. |
output-delay time count count |
By default, a RIPng process sends a maximum of three RIPng packets every 20 milliseconds. |
4. Return to system view. |
quit |
N/A |
5. Enter interface view. |
interface interface-type interface-number |
N/A |
6. Set the interval for sending RIPng packets and the maximum number of RIPng packets that can be sent at each interval. |
ripng output-delay time count count |
By default, an interface uses the RIPng packet sending rate configured for the RIPng process that the interface runs. |
Setting the interval for sending triggered updates
Perform this task to avoid network overhead and reduce system resource consumption caused by frequent RIPng triggered updates.
You can use the timer triggered command to set the maximum interval, minimum interval, and incremental interval for sending RIPng triggered updates.
For a stable network, the minimum interval is used. If network changes become frequent, the triggered update sending interval is incremented by the incremental interval × 2n-2 for each triggered update until the maximum interval is reached. The value n is the number of triggered update times.
To set the interval for sending triggered updates:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIPng view. |
ripng [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Set the interval for sending triggered updates. |
timer triggered maximum-interval [ minimum-interval [ incremental-interval ] ] |
By default: · The maximum interval is 5 seconds. · The minimum interval is 50 milliseconds. · The incremental interval is 200 milliseconds. |
Configuring RIPng GR
Two routers are required to complete a GR process. The following are router roles in a GR process:
· GR restarter—Graceful restarting router. It must have GR capability.
· GR helper—A neighbor of the GR restarter. It helps the GR restarter to complete the GR process.
After RIPng restarts on a router, the router must learn RIPng routes again and updates its FIB table, which causes network disconnections and route reconvergence.
With the GR feature, the restarting router (known as the GR restarter) can notify the event to its GR capable neighbors. GR capable neighbors (known as GR helpers) maintain their adjacencies with the router within a configurable GR interval. During this process, the FIB table of the router does not change. After the restart, the router contacts its neighbors to retrieve its FIB.
By default, a RIPng-enabled device acts as the GR helper. Perform this task on the GR restarter.
|
IMPORTANT: You cannot enable RIPng NSR on a device that acts as GR restarter. |
To configure GR on the GR restarter:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enable RIPng and enter RIPng view. |
ripng [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Enable the GR capability for RIPng. |
graceful-restart |
By default, RIPng GR is disabled. |
4. (Optional.) Set the GR interval. |
graceful-restart interval interval |
By default, the GR interval is 60 seconds. |
Configuring RIPng NSR
Nonstop routing (NSR) backs up RIPng routing information from the active process to the standby process. After an active/standby switchover, NSR can complete route regeneration without tearing down adjacencies or impacting forwarding services.
NSR does not require the cooperation of neighboring devices to recover routing information, and it is typically used more often than GR.
|
IMPORTANT: A device that has RIPng NSR enabled cannot act as GR restarter. |
To enable RIPng NSR:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIPng view. |
ripng [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Enable RIPng NSR. |
non-stop-routing |
By default, RIPng NSR is disabled. RIPng NSR enabled for a RIPng process takes effect only on that process. If multiple RIPng processes exist, enable RIPng NSR for each process as a best practice. |
Configuring RIPng FRR
A link or router failure on a path can cause packet loss and even routing loop until RIPng completes routing convergence based on the new network topology. FRR enables fast rerouting to minimize the impact of link or node failures.
Figure 89 Network diagram for RIPng FRR
As shown in Figure 89, configure FRR on Router B by using a routing policy to specify a backup next hop. When the primary link fails, RIPng directs packets to the backup next hop. At the same time, RIPng calculates the shortest path based on the new network topology. Then, the device forwards packets over that path after network convergence.
Configuration restrictions and guidelines
· RIPng FRR is available only when the state of the primary link (with Layer 3 interfaces staying up) changes from bidirectional to unidirectional or down.
· RIPng FRR is only effective for RIPng routes that are learned from directly connected neighbors.
· Equal-cost routes do not support RIPng FRR.
Configuration prerequisites
You must specify a next hop by using the apply ipv6 fast-reroute backup-interface command in a routing policy and reference the routing policy for FRR. For more information about routing policy configuration, see "Configuring routing policies."
Configuring RIPng FRR
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter RIPng view. |
ripng [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Configure RIPng FRR. |
fast-reroute route-policy route-policy-name |
By default, RIPng FRR is disabled. |
Enabling BFD for RIPng FRR
By default, RIPng FRR does not use BFD to detect primary link failures. To speed up RIPng convergence, enable BFD single-hop echo detection for RIPng FRR to detect primary link failures.
To configure BFD for RIPng FRR:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Configure the source IP address of BFD echo packets. |
bfd echo-source-ipv6 ipv6-address |
By default, the source IP address of BFD echo packets is not configured. The source IP address cannot be on the same network segment as any local interface's IP address. For more information about this command, see High Availability Command Reference. |
3. Enter interface view. |
interface interface-type interface-number |
N/A |
4. Enable BFD for RIPng FRR. |
ripng primary-path-detect bfd echo |
By default, BFD for RIPng FRR is disabled. |
Displaying and maintaining RIPng
Execute display commands in any view and reset commands in user view.
Task |
Command |
Display configuration information for a RIPng process. |
display ripng [ process-id ] |
Display routes in the RIPng database. |
display ripng process-id database [ ipv6-address prefix-length ] |
Display RIPng GR information. |
display ripng [ process-id ] graceful-restart |
Display interface information for a RIPng process. |
display ripng process-id interface [ interface-type interface-number ] |
Display neighbor information for a RIPng process. |
display ripng process-id neighbor [ interface-type interface-number ] |
Display RIPng NSR information. |
display ripng [ process-id ] non-stop-routing |
Display the routing information for a RIPng process. |
display ripng process-id route [ ipv6-address prefix-length [ verbose ] | peer ipv6-address | statistics ] |
Restart a RIPng process. |
reset ripng process-id process |
Clear statistics for a RIPng process. |
reset ripng process-id statistics |
RIPng configuration examples
Basic RIPng configuration example
Network requirements
As shown in Figure 90, Switch A, Switch B, and Switch C run RIPng. Configure Switch B to filter the route 2::/64 learned from Switch A and to forward only the route 4::/64 to Switch A.
Configuration procedure
1. Configure IPv6 addresses for interfaces. (Details not shown.)
2. Configure basic RIPng:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] ripng 1
[SwitchA-ripng-1] quit
[SwitchA] interface vlan-interface 100
[SwitchA-Vlan-interface100] ripng 1 enable
[SwitchA-Vlan-interface100] quit
[SwitchA] interface vlan-interface 400
[SwitchA-Vlan-interface400] ripng 1 enable
[SwitchA-Vlan-interface400] quit
# Configure Switch B.
<SwitchA> system-view
[SwitchA] ripng 1
[SwitchA-ripng-1] quit
[SwitchA] interface vlan-interface 100
[SwitchA-Vlan-interface100] ripng 1 enable
[SwitchA-Vlan-interface100] quit
[SwitchA] interface vlan-interface 400
[SwitchA-Vlan-interface400] ripng 1 enable
[SwitchA-Vlan-interface400] quit
# Configure Switch C.
<SwitchC> system-view
[SwitchC] ripng 1
[SwitchC-ripng-1] quit
[SwitchC] interface vlan-interface 200
[SwitchC-Vlan-interface200] ripng 1 enable
[SwitchC-Vlan-interface200] quit
[SwitchC] interface vlan-interface 500
[SwitchC-Vlan-interface500] ripng 1 enable
[SwitchC-Vlan-interface500] quit
[SwitchC] interface vlan-interface 600
[SwitchC-Vlan-interface600] ripng 1 enable
[SwitchC-Vlan-interface600] quit
# Display the RIPng routing table on Switch B.
[SwitchB] display ripng 1 route
Route Flags: A - Aging, S - Suppressed, G - Garbage-collect, D – Direct
O - Optimal, F - Flush to RIB
----------------------------------------------------------------
Peer FE80::20F:E2FF:FE23:82F5 on Vlan-interface100
Destination 2::/64,
via FE80::20F:E2FF:FE23:82F5, cost 1, tag 0, AOF, 6 secs
Peer FE80::20F:E2FF:FE00:100 on Vlan-interface200
Destination 4::/64,
via FE80::20F:E2FF:FE00:100, cost 1, tag 0, AOF, 11 secs
Destination 5::/64,
via FE80::20F:E2FF:FE00:100, cost 1, tag 0, AOF, 11
Local route
Destination 1::/64,
via ::, cost 0, tag 0, DOF
Destination 3::/64,
via ::, cost 0, tag 0, DOF
# Display the RIPng routing table on Switch A.
[SwitchA] display ripng 1 route
Route Flags: A - Aging, S - Suppressed, G - Garbage-collect, D – Direct
O - Optimal, F - Flush to RIB
----------------------------------------------------------------
Peer FE80::200:2FF:FE64:8904 on Vlan-interface100
Destination 3::/64,
via FE80::200:2FF:FE64:8904, cost 1, tag 0, AOF, 31 secs
Destination 4::/64,
via FE80::200:2FF:FE64:8904, cost 2, tag 0, AOF, 31 secs
Destination 5::/64,
via FE80::200:2FF:FE64:8904, cost 2, tag 0, AOF, 31 secs
Local route
Destination 2::/64,
via ::, cost 0, tag 0, DOF
Destination 1::/64,
via ::, cost 0, tag 0, DOF
3. Configure route filtering:
# Use IPv6 prefix lists on Switch B to filter received and redistributed routes.
[SwitchB] ipv6 prefix-list aaa permit 4:: 64
[SwitchB] ipv6 prefix-list bbb deny 2:: 64
[SwitchB] ipv6 prefix-list bbb permit :: 0 less-equal 128
[SwitchB] ripng 1
[SwitchB-ripng-1] filter-policy prefix-list aaa export
[SwitchB-ripng-1] filter-policy prefix-list bbb import
[SwitchB-ripng-1] quit
# Display RIPng routing tables on Switch B and Switch A.
[SwitchB] display ripng 1 route
Route Flags: A - Aging, S - Suppressed, G - Garbage-collect, D – Direct
O - Optimal, F - Flush to RIB
----------------------------------------------------------------
Peer FE80::1:100 on Vlan-interface100
Peer FE80::3:200 on Vlan-interface200
Destination 4::/64,
via FE80::2:200, cost 1, tag 0, AOF, 11 secs
Destination 5::/64,
via FE80::2:200, cost 1, tag 0, AOF, 11 secs
Local route
Destination 1::/64,
via ::, cost 0, tag 0, DOF
Destination 3::/64,
via ::, cost 0, tag 0, DOF
[SwitchA] display ripng 1 route
Route Flags: A - Aging, S - Suppressed, G - Garbage-collect, D – Direct
O - Optimal, F - Flush to RIB
----------------------------------------------------------------
Peer FE80::2:100 on Vlan-interface100
Destination 4::/64,
via FE80::1:100, cost 2, tag 0, AOF, 2 secs
RIPng route redistribution configuration example
Network requirements
As shown in Figure 91, Switch B communicates with Switch A through RIPng 100 and with Switch C through RIPng 200.
Configure route redistribution on Switch B, so the two RIPng processes can redistribute routes from each other.
Configuration procedure
1. Configure IPv6 addresses for interfaces. (Details not shown.)
2. Configure basic RIPng:
# Enable RIPng 100 on Switch A.
<SwitchA> system-view
[SwitchA] ripng 100
[SwitchA-ripng-100] quit
[SwitchA] interface vlan-interface 100
[SwitchA-Vlan-interface100] ripng 100 enable
[SwitchA-Vlan-interface100] quit
[SwitchA] interface vlan-interface 200
[SwitchA-Vlan-interface200] ripng 100 enable
[SwitchA-Vlan-interface200] quit
# Enable RIPng 100 and RIPng 200 on Switch B.
<SwitchB> system-view
[SwitchB] ripng 100
[SwitchB-ripng-100] quit
[SwitchB] interface vlan-interface 100
[SwitchB-Vlan-interface100] ripng 100 enable
[SwitchB-Vlan-interface100] quit
[SwitchB] ripng 200
[SwitchB-ripng-200] quit
[SwitchB] interface vlan-interface 300
[SwitchB-Vlan-interface300] ripng 200 enable
[SwitchB-Vlan-interface300] quit
# Enable RIPng 200 on Switch C.
<SwitchC> system-view
[SwitchC] ripng 200
[SwitchC] interface vlan-interface 300
[SwitchC-Vlan-interface300] ripng 200 enable
[SwitchC-Vlan-interface300] quit
[SwitchC] interface vlan-interface 400
[SwitchC-Vlan-interface400] ripng 200 enable
[SwitchC-Vlan-interface400] quit
# Display the routing table on Switch A.
[SwitchA] display ipv6 routing-table
Destinations : 7 Routes : 7
Destination: ::1/128 Protocol : Direct
NextHop : ::1 Preference: 0
Interface : InLoop0 Cost : 0
Destination: 1::/64 Protocol : Direct
NextHop : 1::1 Preference: 0
Interface : Vlan100 Cost : 0
Destination: 1::1/128 Protocol : Direct
NextHop : ::1 Preference: 0
Interface : InLoop0 Cost : 0
Destination: 2::/64 Protocol : Direct
NextHop : 2::1 Preference: 0
Interface : Vlan200 Cost : 0
Destination: 2::1/128 Protocol : Direct
NextHop : ::1 Preference: 0
Interface : InLoop0 Cost : 0
Destination: FE80::/10 Protocol : Direct
NextHop : :: Preference: 0
Interface : NULL0 Cost : 0
Destination: FF00::/8 Protocol : Direct
NextHop : :: Preference: 0
Interface : NULL0 Cost : 0
3. Configure RIPng route redistribution:
# Configure route redistribution between the two RIPng processes on Switch B.
[SwitchB] ripng 100
[SwitchB-ripng-100] import-route ripng 200
[SwitchB-ripng-100] quit
[SwitchB] ripng 200
[SwitchB-ripng-200] import-route ripng 100
[SwitchB-ripng-200] quit
# Display the routing table on Switch A.
[SwitchA] display ipv6 routing-table
Destinations : 8 Routes : 8
Destination: ::1/128 Protocol : Direct
NextHop : ::1 Preference: 0
Interface : InLoop0 Cost : 0
Destination: 1::/64 Protocol : Direct
NextHop : 1::1 Preference: 0
Interface : Vlan100 Cost : 0
Destination: 1::1/128 Protocol : Direct
NextHop : ::1 Preference: 0
Interface : InLoop0 Cost : 0
Destination: 2::/64 Protocol : Direct
NextHop : 2::1 Preference: 0
Interface : Vlan200 Cost : 0
Destination: 2::1/128 Protocol : Direct
NextHop : ::1 Preference: 0
Interface : InLoop0 Cost : 0
Destination: 4::/64 Protocol : RIPng
NextHop : FE80::200:BFF:FE01:1C02 Preference: 100
Interface : Vlan100 Cost : 1
Destination: FE80::/10 Protocol : Direct
NextHop : :: Preference: 0
Interface : NULL0 Cost : 0
Destination: FF00::/8 Protocol : Direct
NextHop : :: Preference: 0
Interface : NULL0 Cost : 0
RIPng GR configuration example
Network requirements
As shown in Figure 92, Switch A, Switch B, and Switch C learn IPv6 routing information through RIPng.
Configure Switch A as the GR restarter. Configure Switch B and Switch C as the GR helpers to synchronize their routing tables with Switch A by using GR.
Configuration procedure
1. Configure IPv6 addresses for interfaces. (Details not shown.)
2. Configure RIPng on the switches to ensure the following: (Details not shown.)
? Switch A, Switch B, and Switch C can communicate with each other at Layer 3.
? Dynamic route update can be implemented among them with RIPng.
3. Enable RIPng GR on Switch A.
<SwitchA> system-view
[SwitchA] ripng 1
[SwitchA-ripng-1] graceful-restart
Verifying the configuration
# Restart RIPng process 1 on Switch A.
[SwitchA-ripng-1] return
<SwitchA> reset ripng 1 process
Reset RIPng process? [Y/N]:y
# Display GR information on Switch A.
<SwitchA> display ripng 1 graceful-restart
RIPng process: 1
Graceful Restart capability : Enabled
Current GR state : Normal
Graceful Restart period : 60 seconds
Graceful Restart remaining time: 0 seconds
RIPng NSR configuration example
Network requirements
As shown in Figure 93, Switch S, Switch A, and Switch B learn IPv6 routing information through RIPng.
Enable RIPng NSR on Switch S to ensure correct routing when an active/standby switchover occurs on Switch S.
Configuration procedure
1. Configure IPv6 addresses for interfaces. (Details not shown.)
2. Configure RIPng on the switches to ensure the following: (Details not shown.)
? Switch S, Switch A, and Switch B can communicate with each other at Layer 3.
? Dynamic route update can be implemented among them with RIPng.
3. Enable RIPng NSR on Switch S.
<SwitchS> system-view
[SwitchS] ripng 1
[SwitchS-ripng-1] non-stop-routing
[SwitchS-ripng-1] quit
Verifying the configuration
# Perform an active/standby switchover on Switch S.
[SwitchS] placement reoptimize
Predicted changes to the placement
Program Current location New location
---------------------------------------------------------------------
lb 0/0 0/0
lsm 0/0 0/0
slsp 0/0 0/0
rib6 0/0 0/0
routepolicy 0/0 0/0
rib 0/0 0/0
staticroute6 0/0 0/0
staticroute 0/0 0/0
ospf 0/0 1/0
Continue? [y/n]:y
Re-optimization of the placement start. You will be notified on completion
Re-optimization of the placement complete. Use 'display placement' to view the new placement
# During the switchover period, display RIPng neighbors on Switch A to verify the neighbor relationship between Switch A and Switch S.
[SwitchA] display ripng 1 neighbor
Neighbor Address: FE80::AE45:5CE7:422E:2867
Interface : Vlan-interface100
Version : RIPng version 1 Last update: 00h00m23s
Bad packets: 0 Bad routes : 0
# Display RIPng routes on Switch A to verify if Switch A has a route to the loopback interface on Switch B.
[SwitchA] display ripng 1 route
Route Flags: A - Aging, S - Suppressed, G - Garbage-collect, D - Direct
O - Optimal, F - Flush to RIB
----------------------------------------------------------------
Peer FE80::AE45:5CE7:422E:2867 on Vlan-interface100
Destination 1400:1::/64,
via FE80::AE45:5CE7:422E:2867, cost 1, tag 0, AOF, 1 secs
Destination 4004::4/128,
via FE80::AE45:5CE7:422E:2867, cost 2, tag 0, AOF, 1 secs
Local route
Destination 2002::2/128,
via ::, cost 0, tag 0, DOF
Destination 1200:1::/64,
via ::, cost 0, tag 0, DOF
# Display RIPng neighbors on Switch B to verify the neighbor relationship between Switch B and Switch S.
[SwitchB] display ripng 1 neighbor
Neighbor Address: FE80::20C:29FF:FECE:6277
Interface : Vlan-interface200
Version : RIPng version 1 Last update: 00h00m18s
Bad packets: 0 Bad routes : 0
# Display RIPng routes on Switch B to verify if Switch B has a route to the loopback interface on Switch A.
[SwitchB] display ripng 1 route
Route Flags: A - Aging, S - Suppressed, G - Garbage-collect, D - Direct
O - Optimal, F - Flush to RIB
----------------------------------------------------------------
Peer FE80::20C:29FF:FECE:6277 on Vlan-interface200
Destination 2002::2/128,
via FE80::20C:29FF:FECE:6277, cost 2, tag 0, AOF, 24 secs
Destination 1200:1::/64,
via FE80::20C:29FF:FECE:6277, cost 1, tag 0, AOF, 24 secs
Local route
Destination 4004::4/128,
via ::, cost 0, tag 0, DOF
Destination 1400:1::/64,
via ::, cost 0, tag 0, DOF
The output shows the following when an active/standby switchover occurs on Switch S:
· The neighbor relationships and routing information on Switch A and Switch B have not changed.
· The traffic from Switch A to Switch B has not been impacted.
Configuring RIPng FRR
Network requirements
As shown in Figure 94, Switch A, Switch B, and Switch C run RIPng. Configure RIPng FRR so that when Link A becomes unidirectional, traffic can be switched to Link B immediately.
Device |
Interface |
IP address |
Switch A |
VLAN-interface 100 |
1::1/64 |
Switch A |
VLAN-interface 200 |
2::1/64 |
Switch A |
Loopback 0 |
10::1/128 |
Switch B |
VLAN-interface 101 |
3::1/64 |
Switch B |
VLAN-interface 200 |
2::2/64 |
Switch B |
Loopback 0 |
20::1/128 |
Switch C |
VLAN-interface 100 |
1::2/64 |
Switch C |
VLAN-interface 101 |
3::2/64 |
Configuration procedure
1. Configure IPv6 addresses for interfaces on the switches. (Details not shown.)
2. Configure RIPng on the switches to make sure Switch A, Switch B, and Switch C can communicate with each other at Layer 3. (Details not shown.)
3. Configure RIPng FRR:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] ipv6 prefix-list abc index 10 permit 20::1 128
[SwitchA] route-policy frr permit node 10
[SwitchA-route-policy-frr-10] if-match ipv6 address prefix-list abc
[SwitchA-route-policy-frr-10] apply ipv6 fast-reroute backup-interface vlan-interface 100 backup-nexthop 1::2
[SwitchA-route-policy-frr-10] quit
[SwitchA] ripng 1
[SwitchA-ripng-1] fast-reroute route-policy frr
[SwitchA-ripng-1] quit
# Configure Switch B.
<SwitchB> system-view
[SwitchB] ipv6 prefix-list abc index 10 permit 10::1 128
[SwitchB] route-policy frr permit node 10
[SwitchB-route-policy-frr-10] if-match ipv6 address prefix-list abc
[SwitchB-route-policy-frr-10] apply ipv6 fast-reroute backup-interface vlan-interface 101 backup-nexthop 3::2
[SwitchB-route-policy-frr-10] quit
[SwitchB] ripng 1
[SwitchB-ripng-1] fast-reroute route-policy frr
[SwitchB-ripng-1] quit
Verifying the configuration
# Display the route 20::1/128 on Switch A to view the backup next hop information.
[SwitchA] display ipv6 routing-table 20::1 128 verbose
Summary count : 1
Destination: 20::1/128
Protocol: RIPng
Process ID: 1
SubProtID: 0x0 Age: 00h17m42s
Cost: 1 Preference: 100
IpPre: N/A QosLocalID: N/A
Tag: 0 State: Inactive Adv
OrigTblID: 0x0 OrigVrf: default-vrf
TableID: 0xa OrigAs: 0
NibID: 0x22000003 LastAs: 0
AttrID: 0xffffffff Neighbor: FE80::34CD:9FF:FE2F:D02
Flags: 0x41 OrigNextHop: FE80::34CD:9FF:FE2F:D02
Label: NULL RealNextHop: FE80::34CD:9FF:FE2F:D02
BkLabel: NULL BkNextHop: FE80::7685:45FF:FEAD:102
Tunnel ID: Invalid Interface: Vlan-interface200
BkTunnel ID: Invalid BkInterface: Vlan-interface100
FtnIndex: 0x0 TrafficIndex: N/A
Connector: N/A
# Display the route 10::1/128 on Switch B to view the backup next hop information.
[SwitchB] display ipv6 routing-table 10::1 128 verbose
Summary count : 1
Destination: 10::1/128
Protocol: RIPng
Process ID: 1
SubProtID: 0x0 Age: 00h22m34s
Cost: 1 Preference: 100
IpPre: N/A QosLocalID: N/A
Tag: 0 State: Inactive Adv
OrigTblID: 0x0 OrigVrf: default-vrf
TableID: 0xa OrigAs: 0
NibID: 0x22000001 LastAs: 0
AttrID: 0xffffffff Neighbor: FE80::34CC:E8FF:FE5B:C02
Flags: 0x41 OrigNextHop: FE80::34CC:E8FF:FE5B:C02
Label: NULL RealNextHop: FE80::34CC:E8FF:FE5B:C02
BkLabel: NULL BkNextHop: FE80::7685:45FF:FEAD:102
Tunnel ID: Invalid Interface: Vlan-interface200
BkTunnel ID: Invalid BkInterface: Vlan-interface101
FtnIndex: 0x0 TrafficIndex: N/A
Connector: N/A
Configuring OSPFv3
This chapter describes how to configure RFC 2740-compliant Open Shortest Path First version 3 (OSPFv3) for an IPv6 network. For more information about OSPFv2, see "Configuring OSPF."
Overview
OSPFv3 and OSPFv2 have the following in common:
· 32-bit router ID and area ID.
· Hello, Database Description (DD), Link State Request (LSR), Link State Update (LSU), Link State Acknowledgment (LSAck).
· Mechanisms for finding neighbors and establishing adjacencies.
· Mechanisms for advertising and aging LSAs.
OSPFv3 and OSPFv2 have the following differences:
· OSPFv3 runs on a per-link basis. OSPFv2 runs on a per-IP-subnet basis.
· OSPFv3 supports running multiple processes on an interface, but OSPFv2 does not support.
· OSPFv3 identifies neighbors by router ID. OSPFv2 identifies neighbors by IP address.
OSPFv3 packets
OSPFv3 uses the following packet types:
· Hello—Periodically sent to find and maintain neighbors, containing timer values, information about the DR, BDR, and known neighbors.
· DD—Describes the digest of each LSA in the LSDB, exchanged between two routers for data synchronization.
· LSR—Requests needed LSAs from the neighbor. After exchanging the DD packets, the two routers know which LSAs of the neighbor are missing from their LSDBs. They then send an LSR packet to each other, requesting the missing LSAs. The LSA packet contains the digest of the missing LSAs.
· LSU—Transmits the requested LSAs to the neighbor.
· LSAck—Acknowledges received LSU packets.
OSPFv3 LSA types
OSPFv3 sends routing information in LSAs. The following LSAs are commonly used:
· Router LSA—Type-1 LSA, originated by all routers. This LSA describes the collected states of the router's interfaces to an area, and is flooded throughout a single area only.
· Network LSA—Type-2 LSA, originated for broadcast and NBMA networks by the DR. This LSA contains the list of routers connected to the network, and is flooded throughout a single area only.
· Inter-Area-Prefix LSA—Type-3 LSA, originated by ABRs and flooded throughout the LSA's associated area. Each Inter-Area-Prefix LSA describes a route with IPv6 address prefix to a destination outside the area, yet still inside the AS.
· Inter-Area-Router LSA—Type-4 LSA, originated by ABRs and flooded throughout the LSA's associated area. Each Inter-Area-Router LSA describes a route to ASBR.
· AS External LSA—Type-5 LSA, originated by ASBRs, and flooded throughout the AS, except stub areas and Not-So-Stubby Areas (NSSAs). Each AS External LSA describes a route to another AS. A default route can be described by an AS External LSA.
· NSSA LSA—Type-7 LSA, originated by ASBRs in NSSAs and flooded throughout a single NSSA. NSSA LSAs describe routes to other ASs.
· Link LSA—Type-8 LSA. A router originates a separate Link LSA for each attached link. Link LSAs have link-local flooding scope. Each Link LSA describes the IPv6 address prefix of the link and Link-local address of the router.
· Intra-Area-Prefix LSA—Type-9 LSA. Each Intra-Area-Prefix LSA contains IPv6 prefix information on a router, stub area, or transit area information, and has area flooding scope. It was introduced because Router LSAs and Network LSAs contain no address information.
· Grace LSA—Type-11 LSA, generated by a GR restarter at reboot and transmitted on the local link. The GR restarter describes the cause and interval of the reboot in the Grace LSA to notify its neighbors that it performs a GR operation.
Protocols and standards
· RFC 5340, OSPF for IPv6
· RFC 2328, OSPF Version 2
· RFC 3101, OSPF Not-So-Stubby Area (NSSA) Option
· RFC 5187, OSPFv3 Graceful Restart
OSPFv3 configuration task list
Enabling OSPFv3
Before you enable OSPFv3, configure IPv6 addresses for interfaces to ensure IPv6 connectivity between neighboring nodes.
To enable an OSPFv3 process on a router:
· Enable the OSPFv3 process globally.
· Assign the OSPFv3 process a router ID.
· Enable the OSPFv3 process on related interfaces.
The router ID uniquely identifies the router within an AS. If a router runs multiple OSPFv3 processes, you must specify a unique router ID for each process.
An OSPFv3 process ID has only local significance. Process 1 on a router can exchange packets with process 2 on another router.
To enable OSPFv3:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enable an OSPFv3 process and enter its view. |
ospfv3 [ process-id | vpn-instance vpn-instance-name ] * |
By default, no OSPFv3 processes are enabled. |
3. Specify a router ID. |
router-id router-id |
By default, no router ID is configured. |
4. Enter interface view. |
interface interface-type interface-number |
N/A |
5. Enable an OSPFv3 process on the interface. |
ospfv3 process-id area area-id [ instance instance-id ] |
By default, no OSPFv3 processes are enabled on an interface. |
Configuring OSPFv3 area parameters
OSPFv3 has the same stub area, NSSA area, and virtual link features as OSPFv2.
After you split an OSPFv3 AS into multiple areas, the LSA number is reduced and OSPFv3 applications are extended. To further reduce the size of routing tables and the number of LSAs, configure the non-backbone areas at an AS edge as stub areas.
A stub area cannot import external routes, but an NSSA area can import external routes into the OSPFv3 routing domain while retaining other stub area characteristics.
Non-backbone areas exchange routing information through the backbone area, so the backbone and non-backbone areas (including the backbone itself) must be fully meshed. If no connectivity can be achieved, configure virtual links.
Configuration prerequisites
Before you configure OSPFv3 area parameters, enable OSPFv3.
Configuring a stub area
All the routers attached to a stub area must be configured with the stub command. The no-summary keyword is only available on the ABR of the stub area.
If you use the stub command with the no-summary keyword on an ABR, the ABR advertises a default route in an Inter-Area-Prefix LSA into the stub area. No AS External LSA, Inter-Area-Prefix LSA, or other Inter-Area-Router LSA is advertised in the area. The stub area of this kind is called a totally stub area.
To configure an OSPFv3 stub area:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPFv3 view. |
ospfv3 [ process-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Enter OSPFv3 area view. |
area area-id |
N/A |
4. Configure the area as a stub area. |
stub [ default-route-advertise-always | no-summary ] * |
By default, no area is configured as a stub area. |
5. (Optional.) Set a cost for the default route advertised to the stub area. |
default-cost cost-value |
The default setting is 1. |
Configuring an NSSA area
To configure an NSSA area, configure the nssa command on all the routers attached to the area.
To configure a totally NSSA area, configure the nssa no-summary command on the ABR. The ABR of a totally NSSA area does not advertise inter-area routes into the area.
To configure an NSSA area:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPFv3 view. |
ospfv3 [ process-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Enter OSPFv3 area view. |
area area-id |
N/A |
4. Configure the area as an NSSA area. |
nssa [ default-route-advertise [ cost cost-value | nssa-only | route-policy route-policy-name | tag tag | type type ] * | no-import-route | no-summary | [ translate-always | translate-never ] | suppress-fa | translator-stability-interval value ] * |
By default, no area is configured as an NSSA area. |
5. (Optional.) Set a cost for the default route advertised to the NSSA area. |
default-cost cost-value |
The default setting is 1. This command takes effect only on the ABR/ASBR of an NSSA or totally NSSA area. |
Configuring an OSPFv3 virtual link
You can configure a virtual link to maintain connectivity between a non-backbone area and the backbone, or in the backbone itself.
|
IMPORTANT: · Both ends of a virtual link are ABRs that must be configured with the vlink-peer command. · Do not configure virtual links in the areas of a GR-capable process. |
To configure a virtual link:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPFv3 view. |
ospfv3 [ process-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Enter OSPFv3 area view. |
area area-id |
N/A |
4. Configure a virtual link. |
vlink-peer router-id [ dead seconds | hello seconds | instance instance-id | keychain keychain-name | retransmit seconds | trans-delay seconds ] * |
By default, no virtual links exist. |
Configuring OSPFv3 network types
OSPFv3 classifies networks into the following types by the link layer protocol:
· Broadcast—When the link layer protocol is Ethernet or FDDI, OSPFv3 considers the network type as broadcast by default.
· NBMA—When the link layer protocol is ATM, Frame Relay, or X.25, OSPFv3 considers the network type as NBMA by default.
· P2P—When the link layer protocol is PPP, LAPB, HDLC, or POS, OSPFv3 considers the network type as P2P by default.
Follow these guidelines when you change the network type of an OSPFv3 interface:
· An NBMA network must be fully connected. Any two routers in the network must be directly reachable to each other through a virtual circuit. If no such direct link is available, you must change the network type through a command.
· If direct connections are not available between some routers in an NBMA network, the type of interfaces associated must be configured as P2MP, or as P2P for interfaces with only one neighbor.
Configuration prerequisites
Before you configure OSPFv3 network types, enable OSPFv3.
Configuring the OSPFv3 network type for an interface
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Configure a network type for the OSPFv3 interface. |
ospfv3 network-type { broadcast | nbma | p2mp [ unicast ] | p2p } [ instance instance-id ] |
By default, the network type of an interface depends on the media type of the interface. |
Configuring an NBMA or P2MP neighbor
For NBMA and P2MP interfaces (only when in unicast mode), you must specify the link-local IP addresses of their neighbors because these interfaces cannot find neighbors through broadcasting hello packets. For NBMA interfaces, you can also specify DR priorities for neighbors.
To configure an NBMA or P2MP (unicast) neighbor and its DR priority:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Specify an NBMA or P2MP (unicast) neighbor and its DR priority. |
ospfv3 peer ipv6-address [ cost cost-value | dr-priority priority ] [ instance instance-id ] |
By default, no link-local address is specified for the neighbor interface. |
Configuring OSPFv3 route control
Configuration prerequisites
Before you configure OSPFv3 route control, perform the following tasks:
· Configure IPv6 addresses for interfaces to ensure IPv6 connectivity between neighboring nodes.
· Enable OSPFv3.
Configuring OSPFv3 route summarization
Route summarization enables an ABR or ASBR to summarize contiguous networks into a single network and advertise it to other areas.
Configuring route summarization on an ABR
If contiguous network segments exist in an area, you can summarize them into one network segment on the ABR. The ABR will advertise only the summary route. Any LSA on the specified network segment will not be advertised, reducing the LSDB size in other areas.
To configure route summarization on an ABR:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPFv3 view. |
ospfv3 [ process-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Enter OSPFv3 area view. |
area area-id |
N/A |
4. Configure route summarization on the ABR. |
abr-summary ipv6-address prefix-length [ not-advertise ] [ cost cost-value ] |
By default, route summarization is not configured on an ABR. |
Configuring route summarization on an ASBR
Perform this task to enable an ASBR to summarize external routes within the specified address range into a single route.
An ASBR can summarize routes in the following LSAs:
· Type-5 LSAs.
· Type-7 LSAs in an NSSA area.
· Type-5 LSAs translated by the ASBR (also an ABR) from Type-7 LSAs in an NSSA area.
If the ASBR (ABR) is not a translator, it cannot summarize routes in Type-5 LSAs translated from Type-7 LSAs.
To configure route summarization on an ASBR:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPFv3 view. |
ospfv3 [ process-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Configure route summarization on an ASBR. |
asbr-summary ipv6-address prefix-length [ cost cost-value | not-advertise | nssa-only | tag tag ] * |
By default, route summarization is not configured on an ASBR. |
Configuring OSPFv3 received route filtering
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPFv3 view. |
ospfv3 [ process-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Configure OSPFv3 to filter routes calculated using received LSAs. |
filter-policy { ipv6-acl-number [ gateway prefix-list-name ] | prefix-list prefix-list-name [ gateway prefix-list-name ] | gateway prefix-list-name | route-policy route-policy-name } import |
By default, OSPFv3 accepts all routes calculated using received LSAs. This command can only filter routes computed by OSPFv3. Only routes not filtered out can be added into the local routing table. |
Configuring Inter-Area-Prefix LSA filtering
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPFv3 view. |
ospfv3 [ process-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Enter OSPFv3 area view. |
area area-id |
N/A |
4. Configure OSPFv3 to filter Inter-Area-Prefix LSAs. |
filter { ipv6-acl-number | prefix-list prefix-list-name | route-policy route-policy-name } { export | import } |
By default, OSPFv3 accepts all Inter-Area-Prefix LSAs. This command takes effect only on ABRs. |
Setting an OSPFv3 cost for an interface
You can set an OSPFv3 cost for an interface with one of the following methods:
· Set the cost value in interface view.
· Set a bandwidth reference value for the interface, and OSPFv3 computes the cost automatically based on the bandwidth reference value by using the following formula:
Interface OSPFv3 cost = Bandwidth reference value (100 Mbps) / Interface bandwidth (Mbps)
? If the calculated cost is greater than 65535, the value of 65535 is used.
? If the calculated cost is smaller than 1, the value of 1 is used.
· If no cost is set for an interface, OSPFv3 automatically computes the cost for the interface.
To set an OSPFv3 cost for an interface:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Set an OSPFv3 cost for the interface. |
ospfv3 cost cost-value [ instance instance-id ] |
By default, the OSPFv3 cost is 1 for a VLAN interface, is 0 for a loopback interface. The OSPFv3 cost is automatically computed according to the interface bandwidth for other interfaces. |
To set a bandwidth reference value:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPFv3 view. |
ospfv3 [ process-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Set a bandwidth reference value. |
bandwidth-reference value |
The default setting is 100 Mbps. |
Setting the maximum number of OSPFv3 ECMP routes
Perform this task to implement load sharing over ECMP routes.
To set the maximum number of ECMP routes:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPFv3 view. |
ospfv3 [ process-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Set the maximum number of ECMP routes. |
maximum load-balancing number |
By default, the maximum number of ECMP routes equals the maximum number of ECMP routes supported by the system. |
Setting a preference for OSPFv3
A router can run multiple routing protocols. The system assigns a priority for each protocol. When these routing protocols find the same route, the route found by the protocol with the highest priority is selected.
To set a preference for OSPFv3:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPFv3 view. |
ospfv3 [ process-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Set a preference for OSPFv3. |
preference [ ase ] { preference | route-policy route-policy-name } * |
By default, the preference of OSPFv3 internal routes is 10, and the priority of OSPFv3 external routes is 150. |
Configuring OSPFv3 route redistribution
Because OSPFv3 is a link state routing protocol, it cannot directly filter LSAs to be advertised. OSPFv3 filters only redistributed routes. Only routes that are not filtered out can be advertised in LSAs.
Executing the import-route or default-route-advertise command on a router makes it become an ASBR.
|
IMPORTANT: The import-route bgp4+ command redistributes only EBGP routes. Because the import-route bgp4+ allow-ibgp command redistributes both EBGP and IBGP routes, and might cause routing loops, use it with caution. |
Redistributing routes from another routing protocol
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPFv3 view. |
ospfv3 [ process-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Configure OSPFv3 to redistribute routes from other routing protocols. |
import-route protocol [ as-number ] [ process-id | all-processes | allow-ibgp ] [ allow-direct | cost cost-value | nssa-only | route-policy route-policy-name | tag tag | type type ] * |
By default, route redistribution is disabled. |
4. (Optional.) Configure OSPFv3 to filter redistributed routes. |
filter-policy { ipv6-acl-number | prefix-list prefix-list-name } export [ protocol [ process-id ] ] |
By default, OSPFv3 accepts all redistributed routes. This command filters only routes redistributed with the import-route command. If the import-route command is not configured, executing this command does not take effect. |
Redistributing a default route
The import-route command cannot redistribute a default external route. Perform this task to redistribute a default route.
To redistribute a default route:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPFv3 view. |
ospfv3 [ process-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Redistribute a default route. |
default-route-advertise [ [ always | permit-calculate-other ] | cost cost-value | route-policy route-policy-name | tag tag | type type ] * |
By default, no default route is redistributed. |
Setting tags for redistributed routes
Perform this task to set tags for redistributed routes to identify information about protocols. For example, when redistributing IPv6 BGP routes, OSPFv3 uses tags to identify AS IDs.
To set a tag for redistributed routes:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPFv3 view. |
ospfv3 [ process-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Set a tag for redistributed routes. |
default tag tag |
By default, the tag of redistributed routes is 1. |
Tuning and optimizing OSPFv3 networks
This section describes configurations of OSPFv3 timers, interface DR priority, and the logging of neighbor state changes.
Configuration prerequisites
Before you tune and optimize OSPFv3 networks, perform the following tasks:
· Configure IPv6 addresses for interfaces to ensure IPv6 connectivity between neighboring nodes.
· Enable OSPFv3.
Setting OSPFv3 timers
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Set the hello interval. |
ospfv3 timer hello seconds [ instance instance-id ] |
By default, the hello interval on P2P and broadcast interfaces is 10 seconds. |
4. Set the dead interval. |
ospfv3 timer dead seconds [ instance instance-id ] |
By default, the dead interval on P2P and broadcast interfaces is 40 seconds. The dead interval set on neighboring interfaces cannot be too short. Otherwise, a neighbor is easily considered down. |
5. Set the poll interval. |
ospfv3 timer poll seconds [ instance instance-id ] |
By default, the poll interval is 120 seconds. |
6. Set the LSA retransmission interval. |
ospfv3 timer retransmit interval [ instance instance-id ] |
The default setting is 5 seconds. The LSA retransmission interval cannot be too short. Otherwise, unnecessary retransmissions will occur. |
Setting LSA transmission delay
Each LSA in the LSDB has an age that is incremented by 1 every second, but the age does not change during transmission. Therefore, it is necessary to add a transmission delay into the age time, especially for low-speed links.
To set the LSA transmission delay on an interface:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Set the LSA transmission delay. |
ospfv3 trans-delay seconds [ instance instance-id ] |
By default, the LSA transmission delay is 1 second. |
Setting SPF calculation interval
LSDB changes result in SPF calculations. When the topology changes frequently, a large amount of network and router resources are occupied by SPF calculation. You can adjust the SPF calculation interval to reduce the impact.
For a stable network, the minimum interval is used. If network changes become frequent, the SPF calculation interval is incremented by the incremental interval × 2n-2 for each calculation until the maximum interval is reached. The value n is the number of calculation times.
To set SPF calculation interval:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPFv3 view. |
ospfv3 [ process-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Set the SPF calculation interval. |
spf-schedule-interval maximum-interval [ minimum-interval [ incremental-interval ] ] |
By default: · The maximum interval is 5 seconds. · The minimum interval is 50 milliseconds. · The incremental interval is 200 milliseconds. |
Setting the LSA generation interval
You can adjust the LSA generation interval to protect network resources and routers from being over consumed by frequent network changes.
For a stable network, the minimum interval is used. If network changes become frequent, the LSA generation interval is incremented by the incremental interval × 2n-2 for each generation until the maximum interval is reached. The value n is the number of generation times.
To set the LSA generation interval:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPFv3 view. |
ospfv3 [ process-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Set the LSA generation interval. |
lsa-generation-interval maximum-interval [ minimum-interval [ incremental-interval ] ] |
By default, the maximum interval is 5 seconds, the minimum interval is 0 milliseconds, and the incremental interval is 0 milliseconds. |
Setting a DR priority for an interface
The router priority is used for DR election. Interfaces having the priority 0 cannot become a DR or BDR.
To configure a DR priority for an interface:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Set a router priority. |
ospfv3 dr-priority priority [ instance instance-id ] |
The default router priority is 1. |
Ignoring MTU check for DD packets
When LSAs are few in DD packets, it is unnecessary to check the MTU in DD packets to improve efficiency.
To ignore MTU check for DD packets:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Ignore MTU check for DD packets. |
ospfv3 mtu-ignore [ instance instance-id ] |
By default, OSPFv3 does not ignore MTU check for DD packets. |
Disabling interfaces from receiving and sending OSPFv3 packets
After an OSPFv3 interface is set to silent, direct routes of the interface can still be advertised in Intra-Area-Prefix LSAs through other interfaces, but other OSPFv3 packets cannot be advertised. No neighboring relationship can be established on the interface. This feature can enhance the adaptability of OSPFv3 networking.
To disable interfaces from receiving and sending OSPFv3 packets:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPFv3 view. |
ospfv3 [ process-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Disable interfaces from receiving and sending OSPFv3 packets. |
silent-interface { interface-type interface-number | all } |
By default, the interfaces are able to receive and send OSPFv3 packets. This command disables only the interfaces associated with the current process. However, multiple OSPFv3 processes can disable the same interface from receiving and sending OSPFv3 packets. |
Enabling logging for neighbor state changes
With this feature enabled, the router delivers logs about neighbor state changes to its information center. The information center processes logs according to user-defined output rules (whether to output logs and where to output). For more information about the information center, see Network Management and Monitoring Configuration Guide.
To enable logging for neighbor state changes:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPFv3 view. |
ospfv3 [ process-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Enable logging for neighbor state changes. |
log-peer-change |
By default, this feature is enabled. |
Configuring OSPFv3 network management
This task involves the following configurations:
· Bind an OSPFv3 process to MIB so that you can use network management software to manage the specified OSPFv3 process.
· Enable SNMP notifications for OSPFv3 to report important events.
· Set the SNMP notification output interval and the maximum number of SNMP notifications that can be output at each interval.
To report critical OSPFv3 events to an NMS, enable SNMP notifications for OSPFv3. For SNMP notifications to be sent correctly, you must also configure SNMP on the device. For more information about SNMP configuration, see the network management and monitoring configuration guide for the device.
The standard OSPFv3 MIB provides only single-instance MIB objects. To identify multiple OSPFv3 processes in the standard OSPFv3 MIB, you must assign a unique context name to each OSPFv3 process.
Context is a method introduced to SNMPv3 for multiple-instance management. For SNMPv1/v2c, you must specify a community name as a context name for protocol identification.
To configure OSPFv3 network management:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Bind MIB to an OSPFv3 process. |
ospfv3 mib-binding process-id |
By default, MIB is bound to the process with the smallest process ID. |
3. Enable SNMP notifications for OSPFv3. |
snmp-agent trap enable ospfv3 [ grrestarter-status-change | grhelper-status-change | if-state-change | if-cfg-error | if-bad-pkt | neighbor-state-change | nssatranslator-status-change | virtif-bad-pkt | virtif-cfg-error | virtif-state-change | virtgrhelper-status-change | virtneighbor-state-change ]* |
By default, SNMP notifications for OSPFv3 are enabled. |
4. Enter OSPFv3 view. |
ospfv3 [ process-id | vpn-instance vpn-instance-name ] * |
N/A |
5. Configure an SNMP context for the OSPFv3 process. |
snmp context-name context-name |
By default, no SNMP context is configured for the OSPFv3 process. |
6. (Optional.) Set the SNMP notification output interval and the maximum number of SNMP notifications that can be output at each interval. |
snmp trap rate-limit interval trap-interval count trap-number |
By default, OSPFv3 outputs a maximum of seven SNMP notifications within 10 seconds. |
Setting the LSU transmit rate
Sending large numbers of LSU packets affects router performance and consumes a large amount of network bandwidth. You can configure the router to send LSU packets at an interval and to limit the maximum number of LSU packets sent out of an OSPFv3 interface at each interval.
To set the LSU transmit rate:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPFv3 view. |
ospfv3 [ process-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Set the LSU transmit rate. |
transmit-pacing interval interval count count |
By default, an OSPFv3 interface sends a maximum of three LSU packets every 20 milliseconds. |
Configuring stub routers
A stub router is used for traffic control. It reports its status as a stub router to neighboring OSPFv3 routers. The neighboring routers can have a route to the stub router, but they do not use the stub router to forward data.
Use either of the following methods to configure a router as a stub router:
· Clear the R-bit of the Option field in Type-1 LSAs. When the R-bit is clear, the OSPFv3 router can participate in OSPFv3 topology distribution without forwarding traffic.
· Use the OSPFv3 max-metric router LSA feature. This feature enables OSPFv3 to advertise its locally generated Type-1 LSAs with a maximum cost of 65535. Neighbors do not send packets to the stub router as long as they have a route with a smaller cost.
To configure a router as a stub router:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPFv3 view. |
ospfv3 [ process-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Configure the router as a stub router. |
·
Method 1: ·
Method 2: |
By default, the router is not configured as a stub router. A stub router is not related to a stub area. |
Configuring prefix suppression
By default, an OSPFv3 interface advertises all of its prefixes in LSAs. To speed up OSPFv3 convergence, you can suppress interfaces from advertising all of their prefixes. This feature helps improve network security by preventing IP routing to the suppressed networks.
When prefix suppression is enabled:
· OSPFv3 does not advertise the prefixes of suppressed interfaces in Type-8 LSAs.
· On broadcast and NBMA networks, the DR does not advertise the prefixes of suppressed interfaces in Type-9 LSAs that reference Type-2 LSAs.
· On P2P and P2MP networks, OSPFv3 does not advertise the prefixes of suppressed interfaces in Type-9 LSAs that reference Type-1 LSAs.
|
IMPORTANT: As a best practice, configure prefix suppression on all OSPFv3 routers if you want to use prefix suppression. |
Configuring prefix suppression for an OSPFv3 process
Enabling prefix suppression for an OSPFv3 process does not suppress the prefixes of loopback interfaces and passive interfaces.
To configure prefix suppression for an OSPFv3 process:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPFv3 view. |
ospfv3 [ process-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Enable prefix suppression for the OSPFv3 process. |
prefix-suppression |
By default, prefix suppression is disabled for an OSPFv3 process. |
Configuring prefix suppression for an interface
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Enable prefix suppression for the interface. |
ospfv3 prefix-suppression [ disable ] [ instance instance-id ] |
By default, prefix suppression is disabled for an interface. |
Setting the maximum number of OSPFv3 logs
OSPFv3 logs include route calculation logs, neighbor logs, and LSA aging logs.
To set the maximum number of OSPFv3 logs:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPFv3 view. |
ospfv3 [ process-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Set the maximum number of OSPFv3 logs. |
event-log { lsa-flush | peer | spf } size count |
By default, the maximum number of LSA aging logs, neighbor logs, or route calculation logs is 10. |
Configuring OSPFv3 authentication
OSPFv3 uses keychain authentication to prevent routing information from being leaked and routers from being attacked.
OSPFv3 adds the Authentication Trailer option into outgoing packets, and uses the authentication information in the option to authenticate incoming packets. Only packets that pass the authentication can be received. If a packet fails the authentication, the OSPFv3 neighbor relationship cannot be established.
The authentication mode specified for an OSPFv3 interface has a higher priority than the mode specified for an OSPFv3 area.
Configuring OSPFv3 area authentication
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPFv3 view. |
ospfv3 [ process-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Enter OSPFv3 area view. |
area area-id |
N/A |
4. Specify an authentication mode for the area. |
authentication-mode keychain keychain-name |
By default, no authentication is performed for the area. For more information about keychains, see Security Configuration Guide. |
Configuring OSPFv3 interface authentication
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Specify an authentication mode for the interface. |
ospfv3 authentication-mode keychain keychain-name [ instance instance-id ] |
By default, no authentication is performed for the interface. For more information about keychains, see Security Configuration Guide. |
Configuring OSPFv3 GR
GR ensures forwarding continuity when a routing protocol restarts or an active/standby switchover occurs.
Two routers are required to complete a GR process. The following are router roles in a GR process:
· GR restarter—Graceful restarting router. It must be Graceful Restart capable.
· GR helper—The neighbor of the GR restarter. It helps the GR restarter to complete the GR process.
To prevent service interruption after a master/backup switchover, a GR restarter running OSPFv3 must perform the following tasks:
· Keep the GR restarter forwarding entries stable during reboot.
· Establish all adjacencies and obtain complete topology information after reboot.
After the active/standby switchover, the GR restarter sends a Grace LSA to tell its neighbors that it performs a GR. Upon receiving the Grace LSA, the neighbors with the GR helper capability enter the helper mode (and are called GR helpers). Then, the GR restarter retrieves its adjacencies and LSDB with the help of the GR helpers.
Configuring GR restarter
You can configure the GR restarter capability on a GR restarter.
|
IMPORTANT: You cannot enable OSPFv3 NSR on a device that acts as GR restarter. |
To configure GR restarter:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPFv3 view. |
ospfv3 [ process-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Enable the GR capability. |
graceful-restart enable [ global | planned-only ] * |
By default, OSPFv3 GR restarter capability is disabled. |
4. (Optional.) Set the GR interval. |
graceful-restart interval interval |
By default, the GR interval is 120 seconds. |
Configuring GR helper
You can configure the GR helper capability on a GR helper.
To configure GR helper:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPFv3 view. |
ospfv3 [ process-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Enable the GR helper capability. |
graceful-restart helper enable [ planned-only ] |
By default, the GR helper capability is enabled. |
4. Enable strict LSA checking. |
graceful-restart helper strict-lsa-checking |
By default, strict LSA checking is disabled. |
Triggering OSPFv3 GR
OSPFv3 GR is triggered by an active/standby switchover or when the following command is executed.
To trigger OSPFv3 GR, perform the following command in user view:
Task |
Command |
Trigger OSPFv3 GR. |
reset ospfv3 [ process-id ] process graceful-restart |
Configuring OSPFv3 NSR
Nonstop routing (NSR) backs up OSPFv3 link state information from the active process to the standby process. After an active/standby switchover, NSR can complete link state recovery and route regeneration without tearing down adjacencies or impacting forwarding services.
NSR does not require the cooperation of neighboring devices to recover routing information, and it is typically used more often than GR.
|
IMPORTANT: A device that has OSPFv3 NSR enabled cannot act as GR restarter. |
To enable OSPFv3 NSR:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPFv3 view. |
ospfv3 [ process-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Enable OSPFv3 NSR. |
non-stop-routing |
By default, OSPFv3 NSR is disabled. This command takes effect only for the current process. As a best practice, enable OSPFv3 NSR for each process if multiple OSPFv3 processes exist. |
Configuring BFD for OSPFv3
Bidirectional forwarding detection (BFD) provides a mechanism to quickly detect the connectivity of links between OSPFv3 neighbors, improving the convergence speed of OSPFv3. For more information about BFD, see High Availability Configuration Guide.
After discovering neighbors by sending hello packets, OSPFv3 notifies BFD of the neighbor addresses, and BFD uses these addresses to establish sessions. Before a BFD session is established, it is in the down state. In this state, BFD control packets are sent at an interval of no less than 1 second to reduce BFD control packet traffic. After the BFD session is established, BFD control packets are sent at the negotiated interval, thereby implementing fast fault detection.
To configure BFD for OSPFv3, you need to configure OSPFv3 first.
To configure BFD for OSPFv3:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter OSPFv3 view. |
ospfv3 [ process-id | vpn-instance vpn-instance-name ] * |
N/A |
3. Specify a router ID. |
router-id router-id |
N/A |
4. Quit the OSPFv3 view. |
quit |
N/A |
5. Enter interface view. |
interface interface-type interface-number |
N/A |
6. Enable an OSPFv3 process on the interface. |
ospfv3 process-id area area-id [ instance instance-id ] |
N/A |
7. Enable BFD on the interface. |
ospfv3 bfd enable [ instance instance-id ] |
By default, BFD is disabled on the OSPFv3 interface. |
Configuring OSPFv3 FRR
A primary link failure can cause packet loss and even a routing loop until OSPFv3 completes routing convergence based on the new network topology. OSPFv3 FRR enables fast rerouting to minimize the failover time.
Figure 95 Network diagram for OSPFv3 FRR
As shown in Figure 95, configure FRR on Router B. OSPFv3 FRR automatically calculates a backup next hop or specifies a backup next hop by using a routing policy. When the primary link fails, OSPFv3 directs packets to the backup next hop. At the same time, OSPFv3 calculates the shortest path based on the new network topology. It forwards packets over the path after network convergence.
You can configure OSPFv3 FRR to calculate a backup next hop by using the loop free alternate (LFA) algorithm, or specify a backup next hop by using a routing policy.
Configuration prerequisites
Before you configure OSPFv3 FRR, perform the following tasks:
· Configure IPv6 addresses for interfaces to ensure IP connectivity between neighboring nodes.
· Enable OSPFv3.
· Make sure the backup next hop is reachable.
Configuration guidelines
Do not use the fast-reroute lfa command together with the vlink-peer command.
Configuration procedure
Configuring OSPFv3 FRR to calculate a backup next hop using the LFA algorithm
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. (Optional.) Disable LFA on an interface. |
ospfv3 fast-reroute lfa-backup exclude |
By default, the interface on which LFA is enabled can be selected as a backup interface. |
4. Return to system view. |
quit |
N/A |
5. Enter OSPFv3 view. |
ospfv3 [ process-id | vpn-instance vpn-instance-name ] * |
N/A |
6. Enable OSPFv3 FRR to calculate a backup next hop by using the LFA algorithm. |
fast-reroute lfa [ abr-only ] |
By default, OSPFv3 FRR is disabled. If abr-only is specified, the route to the ABR is selected as the backup path. |
Configuring OSPFv3 FRR to specify a backup next hop using a routing policy
Before you perform this task, use the apply ipv6 fast-reroute backup-interface command to specify a backup next hop in the routing policy to be used. For more information about the apply ipv6 fast-reroute backup-interface command and routing policy configuration, see "Configuring routing policies."
To configure OSPFv3 FRR to specify a backup next hop using a routing policy:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. (Optional.) Disable LFA on an interface. |
ospfv3 fast-reroute lfa-backup exclude |
By default, the interface is enabled with LFA and it can be selected as a backup interface. |
4. Return to system view. |
quit |
N/A |
5. Enter OSPFv3 view. |
ospfv3 [ process-id | vpn-instance vpn-instance-name ] * |
N/A |
6. Enable OSPFv3 FRR to specify a backup next hop by using a routing policy. |
fast-reroute route-policy route-policy-name |
By default, OSPFv3 FRR is disabled. |
Configuring BFD for OSPFv3 FRR
By default, OSPFv3 FRR does not use BFD to detect primary link failures. To speed up OSPFv3 convergence, enable BFD for OSPFv3 FRR to detect primary link failures.
To configure BFD control packet mode for OSPFv3 FRR:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Enable BFD control packet mode for OSPFv3 FRR. |
ospfv3 primary-path-detect bfd ctrl [ instance instance-id ] |
By default, BFD control packet mode for OSPFv3 FRR is disabled. |
To configure BFD echo packet mode for OSPFv3 FRR:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Configure the source IPv6 address of BFD echo packets. |
bfd echo-source-ipv6 ipv6-address |
By default, the source IPv6 address of BFD echo packets is not configured. The source IPv6 address cannot be on the same network segment as any local interface's IP address. For more information about this command, see High Availability Command Reference. |
3. Enter interface view. |
interface interface-type interface-number |
N/A |
4. Enable BFD echo packet mode for OSPFv3 FRR. |
ospfv3 primary-path-detect bfd echo [ instance instance-id ] |
By default, BFD echo packet mode for OSPFv3 FRR is disabled. |
Displaying and maintaining OSPFv3
Execute display commands in any view and reset commands in user view.
Task |
Command |
Display information about the routes to OSPFv3 ABR and ASBR. |
display ospfv3 [ process-id ] abr-asbr |
Display summary route information on the OSPFv3 ABR. |
display ospfv3 [ process-id ] [ area area-id ] abr-summary [ ipv6-address prefix-length ] [ verbose ] |
Display summary route information on the OSPFv3 ASBR. |
display ospfv3 [ process-id ] asbr-summary [ ipv6-address prefix-length ] [ verbose ] |
Display OSPFv3 log information. |
display ospfv3 [ process-id ] event-log { lsa-flush | peer | spf } |
Display OSPFv3 process information. |
display ospfv3 [ process-id ] [ verbose ] |
Display OSPFv3 GR information. |
display ospfv3 [ process-id ] graceful-restart [ verbose ] |
Display OSPFv3 NSR information. |
display ospfv3 [ process-id ] non-stop-routing |
Display OSPFv3 interface information. |
display ospfv3 [ process-id ] interface [ interface-type interface-number | verbose ] |
Display OSPFv3 LSDB information. |
display ospfv3 [ process-id ] lsdb [ { external | grace | inter-prefix | inter-router | intra-prefix | link | network | nssa | router | unknown [ type ] } [ link-state-id ] [ originate-router router-id | self-originate ] | statistics | total | verbose ] |
Display OSPFv3 next hop information. |
display ospfv3 [ process-id ] nexthop |
Display OSPFv3 neighbor information. |
display ospfv3 [ process-id ] [ area area-id ] peer [ [ interface-type interface-number ] [ verbose ] | peer-router-id | statistics ] |
Display OSPFv3 request list information. |
display ospfv3 [ process-id ] [ area area-id ] request-queue [ interface-type interface-number ] [ neighbor-id ] |
Display OSPFv3 retransmission list information. |
display ospfv3 [ process-id ] [ area area-id ] retrans-queue [ interface-type interface-number ] [ neighbor-id ] |
Display OSPFv3 routing information. |
display ospfv3 [ process-id ] routing [ ipv6-address prefix-length ] |
Display OSPFv3 topology information. |
display ospfv3 [ process-id ] [ area area-id ] spf-tree [ verbose ] |
Display OSPFv3 statistics. |
display ospfv3 [ process-id ] statistics [ error ] |
Display OSPFv3 virtual link information. |
display ospfv3 [ process-id ] vlink |
Restart an OSPFv3 process. |
reset ospfv3 [ process-id ] process [ graceful-restart ] |
Restart OSPFv3 route redistribution. |
reset ospfv3 [ process-id ] redistribution |
Clear OSPFv3 statistics. |
reset ospfv3 [ process-id ] statistics |
Clear OSPFv3 logs. |
reset ospfv3 [ process-id ] event-log [ lsa-flush | peer | spf ] |
OSPFv3 configuration examples
OSPFv3 stub area configuration example
Network requirements
As shown in Figure 96:
· Enable OSPFv3 on all switches.
· Split the AS into three areas.
· Configure Switch B and Switch C as ABRs to forward routing information between areas.
· Configure Area 2 as a stub area to reduce LSAs in the area without affecting route reachability.
Configuration procedure
1. Configure IPv6 addresses for interfaces. (Details not shown.)
2. Configure basic OSPFv3:
# On Switch A, enable OSPFv3 and specify the router ID as 1.1.1.1.
<SwitchA> system-view
[SwitchA] ospfv3
[SwitchA-ospfv3-1] router-id 1.1.1.1
[SwitchA-ospfv3-1] quit
[SwitchA] interface vlan-interface 300
[SwitchA-Vlan-interface300] ospfv3 1 area 1
[SwitchA-Vlan-interface300] quit
[SwitchA] interface vlan-interface 200
[SwitchA-Vlan-interface200] ospfv3 1 area 1
[SwitchA-Vlan-interface200] quit
# On Switch B, enable OSPFv3 and specify the router ID as 2.2.2.2.
<SwitchB> system-view
[SwitchB] ospfv3
[SwitchB-ospfv3-1] router-id 2.2.2.2
[SwitchB-ospfv3-1] quit
[SwitchB] interface vlan-interface 100
[SwitchB-Vlan-interface100] ospfv3 1 area 0
[SwitchB-Vlan-interface100] quit
[SwitchB] interface vlan-interface 200
[SwitchB-Vlan-interface200] ospfv3 1 area 1
[SwitchB-Vlan-interface200] quit
# On Switch C, enable OSPFv3 and specify the router ID as 3.3.3.3.
<SwitchC> system-view
[SwitchC] ospfv3
[SwitchC-ospfv3-1] router-id 3.3.3.3
[SwitchC-ospfv3-1] quit
[SwitchC] interface vlan-interface 100
[SwitchC-Vlan-interface100] ospfv3 1 area 0
[SwitchC-Vlan-interface100] quit
[SwitchC] interface vlan-interface 400
[SwitchC-Vlan-interface400] ospfv3 1 area 2
[SwitchC-Vlan-interface400] quit
# On Switch D, enable OSPFv3 and specify the router ID as 4.4.4.4.
<SwitchD> system-view
[SwitchD] ospfv3
[SwitchD-ospfv3-1] router-id 4.4.4.4
[SwitchD-ospfv3-1] quit
[SwitchD] interface vlan-interface 400
[SwitchD-Vlan-interface400] ospfv3 1 area 2
[SwitchD-Vlan-interface400] quit
# Display OSPFv3 neighbors on Switch B.
[SwitchB] display ospfv3 peer
OSPFv3 Process 1 with Router ID 2.2.2.2
Area: 0.0.0.0
-------------------------------------------------------------------------
Router ID Pri State Dead-Time InstID Interface
3.3.3.3 1 Full/BDR 00:00:40 0 Vlan100
Area: 0.0.0.1
-------------------------------------------------------------------------
Router ID Pri State Dead-Time InstID Interface
1.1.1.1 1 Full/DR 00:00:40 0 Vlan200
# Display OSPFv3 neighbors on Switch C.
[SwitchC] display ospfv3 peer
OSPFv3 Process 1 with Router ID 3.3.3.3
Area: 0.0.0.0
-------------------------------------------------------------------------
Router ID Pri State Dead-Time InstID Interface
2.2.2.2 1 Full/DR 00:00:40 0 Vlan100
Area: 0.0.0.2
-------------------------------------------------------------------------
Router ID Pri State Dead-Time InstID Interface
4.4.4.4 1 Full/BDR 00:00:40 0 Vlan400
# Display OSPFv3 routing table information on Switch D.
[SwitchD] display ospfv3 routing
OSPFv3 Process 1 with Router ID 4.4.4.4
-------------------------------------------------------------------------
I - Intra area route, E1 - Type 1 external route, N1 - Type 1 NSSA route
IA - Inter area route, E2 - Type 2 external route, N2 - Type 2 NSSA route
* - Selected route
*Destination: 2001::/64
Type : IA Cost : 2
NextHop : FE80::F40D:0:93D0:1 Interface: Vlan400
AdvRouter : 3.3.3.3 Area : 0.0.0.2
Preference : 10
*Destination: 2001:1::/64
Type : IA Cost : 3
NextHop : FE80::F40D:0:93D0:1 Interface: Vlan400
AdvRouter : 3.3.3.3 Area : 0.0.0.2
Preference : 10
*Destination: 2001:2::/64
Type : I Cost : 1
Nexthop : :: Interface: Vlan400
AdvRouter : 4.4.4.4 Area : 0.0.0.2
Preference : 10
*Destination: 2001:3::/64
Type : IA Cost : 4
NextHop : FE80::F40D:0:93D0:1 Interface: Vlan400
AdvRouter : 3.3.3.3 Area : 0.0.0.2
Preference : 10
Total: 4
Intra area: 1 Inter area: 3 ASE: 0 NSSA: 0
3. Configure Area 2 as a stub area:
# Configure Switch D.
[SwitchD] ospfv3
[SwitchD-ospfv3-1] area 2
[SwitchD-ospfv3-1-area-0.0.0.2] stub
# Configure Switch C, and specify the cost of the default route sent to the stub area as 10.
[SwitchC] ospfv3
[SwitchC-ospfv3-1] area 2
[SwitchC-ospfv3-1-area-0.0.0.2] stub
[SwitchC-ospfv3-1-area-0.0.0.2] default-cost 10
# Display OSPFv3 routing table information on Switch D.
[SwitchD] display ospfv3 routing
OSPFv3 Process 1 with Router ID 4.4.4.4
-------------------------------------------------------------------------
I - Intra area route, E1 - Type 1 external route, N1 - Type 1 NSSA route
IA - Inter area route, E2 - Type 2 external route, N2 - Type 2 NSSA route
* - Selected route
*Destination: ::/0
Type : IA Cost : 11
NextHop : FE80::F40D:0:93D0:1 Interface: Vlan400
AdvRouter : 4.4.4.4 Area : 0.0.0.2
Preference : 10
*Destination: 2001::/64
Type : IA Cost : 2
NextHop : FE80::F40D:0:93D0:1 Interface: Vlan400
AdvRouter : 3.3.3.3 Area : 0.0.0.2
Preference : 10
*Destination: 2001:1::/64
Type : IA Cost : 3
NextHop : FE80::F40D:0:93D0:1 Interface: Vlan400
AdvRouter : 3.3.3.3 Area : 0.0.0.2
Preference : 10
*Destination: 2001:2::/64
Type : I Cost : 1
Nexthop : :: Interface: Vlan400
AdvRouter : 4.4.4.4 Area : 0.0.0.2
Preference : 10
*Destination: 2001:3::/64
Type : IA Cost : 4
NextHop : FE80::F40D:0:93D0:1 Interface: Vlan400
AdvRouter : 3.3.3.3 Area : 0.0.0.2
Preference : 10
Total: 5
Intra area: 1 Inter area: 4 ASE: 0 NSSA: 0
The output shows that a default route is added, and its cost is the cost of a direct route plus the configured cost.
4. Configure Area 2 as a totally stub area:
# Configure Area 2 as a totally stub area on Switch C.
[SwitchC-ospfv3-1-area-0.0.0.2] stub no-summary
# Display OSPFv3 routing table information on Switch D.
[SwitchD] display ospfv3 routing
OSPFv3 Process 1 with Router ID 4.4.4.4
-------------------------------------------------------------------------
I - Intra area route, E1 - Type 1 external route, N1 - Type 1 NSSA route
IA - Inter area route, E2 - Type 2 external route, N2 - Type 2 NSSA route
* - Selected route
*Destination: ::/0
Type : IA Cost : 11
NextHop : FE80::F40D:0:93D0:1 Interface: Vlan400
AdvRouter : 4.4.4.4 Area : 0.0.0.2
Preference : 10
*Destination: 2001:2::/64
Type : I Cost : 1
Nexthop : :: Interface: Vlan400
AdvRouter : 4.4.4.4 Area : 0.0.0.2
Preference : 10
Total: 2
Intra area: 1 Inter area: 1 ASE: 0 NSSA: 0
The output shows that route entries are reduced. All indirect routes are removed, except the default route.
OSPFv3 NSSA area configuration example
Network requirements
As shown in Figure 97:
· Configure OSPFv3 on all switches and split the AS into three areas.
· Configure Switch B and Switch C as ABRs to forward routing information between areas.
· Configure Area 1 as an NSSA area and configure Switch A as an ASBR to redistribute static routes into the AS.
Configuration procedure
1. Configure IPv6 addresses for interfaces. (Details not shown.)
2. Configure basic OSPFv3 (see "OSPFv3 stub area configuration example").
3. Configure Area 1 as an NSSA area:
# Configure Switch A.
[SwitchA] ospfv3
[SwitchA-ospfv3-1] area 1
[SwitchA-ospfv3-1-area-0.0.0.1] nssa
[SwitchA-ospfv3-1-area-0.0.0.1] quit
[SwitchA-ospfv3-1] quit
# Configure Switch B.
[SwitchB] ospfv3
[SwitchB-ospfv3-1] area 1
[SwitchB-ospfv3-1-area-0.0.0.1] nssa
[SwitchB-ospfv3-1-area-0.0.0.1] quit
[SwitchB-ospfv3-1] quit
# Display OSPFv3 routing information on Switch A.
[SwitchA] display ospfv3 1 routing
OSPFv3 Process 1 with Router ID 1.1.1.1
-------------------------------------------------------------------------
I - Intra area route, E1 - Type 1 external route, N1 - Type 1 NSSA route
IA - Inter area route, E2 - Type 2 external route, N2 - Type 2 NSSA route
* - Selected route
*Destination: 2001::/64
Type : IA Cost : 2
NextHop : FE80::20C:29FF:FE74:59C6 Interface: Vlan200
AdvRouter : 2.2.2.2 Area : 0.0.0.1
Preference : 10
*Destination: 2001:1::/64
Type : I Cost : 1
Nexthop : :: Interface: Vlan200
AdvRouter : 1.1.1.1 Area : 0.0.0.1
Preference : 10
*Destination: 2001:2::/64
Type : IA Cost : 3
NextHop : FE80::20C:29FF:FE74:59C6 Interface: Vlan200
AdvRouter : 2.2.2.2 Area : 0.0.0.1
Preference : 10
Total: 3
Intra area: 1 Inter area: 2 ASE: 0 NSSA: 0
4. Configure route redistribution:
# Configure an IPv6 static route, and configure OSPFv3 to redistribute the static route on Switch A.
[SwitchA] ipv6 route-static 1234:: 64 null 0
[SwitchA] ospfv3 1
[SwitchA-ospfv3-1] import-route static
[SwitchA-ospfv3-1] quit
# Display OSPFv3 routing information on Switch D.
[SwitchD] display ospfv3 1 routing
OSPFv3 Process 1 with Router ID 4.4.4.4
-------------------------------------------------------------------------
I - Intra area route, E1 - Type 1 external route, N1 - Type 1 NSSA route
IA - Inter area route, E2 - Type 2 external route, N2 - Type 2 NSSA route
* - Selected route
*Destination: 2001::/64
Type : IA Cost : 2
NextHop : FE80::20C:29FF:FEB9:F2EF Interface: Vlan400
AdvRouter : 3.3.3.3 Area : 0.0.0.2
Preference : 10
*Destination: 2001:1::/64
Type : IA Cost : 3
NextHop : FE80::20C:29FF:FEB9:F2EF Interface: Vlan400
AdvRouter : 3.3.3.3 Area : 0.0.0.2
Preference : 10
*Destination: 2001:2::/64
Type : I Cost : 1
NextHop : :: Interface: Vlan400
AdvRouter : 4.4.4.4 Area : 0.0.0.2
Preference : 10
*Destination: 1234::/64
Type : E2 Cost : 1
NextHop : FE80::20C:29FF:FEB9:F2EF Interface: Vlan400
AdvRouter : 2.2.2.2 Area : 0.0.0.2
Preference : 10
Total: 4
Intra area: 1 Inter area: 2 ASE: 1 NSSA: 0
The output shows an AS external route imported from the NSSA area exists on Switch D.
OSPFv3 DR election configuration example
Network requirements
As shown in Figure 98:
· Configure router priority 100 for Switch A, the highest priority on the network, so it will become the DR.
· Configure router priority 2 for Switch C, the second highest priority on the network, so it will become the BDR.
· Configure router priority 0 for Switch B, so it cannot become a DR or BDR.
· Switch D uses the default router priority 1.
Configuration procedure
1. Configure IPv6 addresses for interfaces. (Details not shown.)
2. Configure basic OSPFv3:
# On Switch A, enable OSPFv3 and specify the router ID as 1.1.1.1.
<SwitchA> system-view
[SwitchA] ospfv3
[SwitchA-ospfv3-1] router-id 1.1.1.1
[SwitchA-ospfv3-1] quit
[SwitchA] interface vlan-interface 100
[SwitchA-Vlan-interface100] ospfv3 1 area 0
[SwitchA-Vlan-interface100] quit
# On Switch B, enable OSPFv3 and specify the router ID as 2.2.2.2.
<SwitchB> system-view
[SwitchB] ospfv3
[SwitchB-ospfv3-1] router-id 2.2.2.2
[SwitchB-ospfv3-1] quit
[SwitchB] interface vlan-interface 200
[SwitchB-Vlan-interface200] ospfv3 1 area 0
[SwitchB-Vlan-interface200] quit
# On Switch C, enable OSPFv3 and specify the router ID as 3.3.3.3.
<SwitchC> system-view
[SwitchC] ospfv3
[SwitchC-ospfv3-1] router-id 3.3.3.3
[SwitchC-ospfv3-1] quit
[SwitchC] interface vlan-interface 100
[SwitchC-Vlan-interface100] ospfv3 1 area 0
[SwitchC-Vlan-interface100] quit
# On Switch D, enable OSPFv3 and specify the router ID as 4.4.4.4.
<SwitchD> system-view
[SwitchD] ospfv3
[SwitchD-ospfv3-1] router-id 4.4.4.4
[SwitchD-ospfv3-1] quit
[SwitchD] interface vlan-interface 200
[SwitchD-Vlan-interface200] ospfv3 1 area 0
[SwitchD-Vlan-interface200] quit
# Display neighbor information on Switch A. The switches have the same default DR priority 1, so Switch D (the switch with the highest router ID) is elected as the DR, and Switch C is the BDR.
[SwitchA] display ospfv3 peer
OSPFv3 Process 1 with Router ID 1.1.1.1
Area: 0.0.0.0
-------------------------------------------------------------------------
Router ID Pri State Dead-Time InstID Interface
2.2.2.2 1 2-Way/DROther 00:00:36 0 Vlan200
3.3.3.3 1 Full/BDR 00:00:35 0 Vlan100
4.4.4.4 1 Full/DR 00:00:33 0 Vlan200
# Display neighbor information on Switch D. The neighbor states are all full.
[SwitchD] display ospfv3 peer
OSPFv3 Process 1 with Router ID 4.4.4.4
Area: 0.0.0.0
-------------------------------------------------------------------------
Router ID Pri State Dead-Time InstID Interface
1.1.1.1 1 Full/DROther 00:00:30 0 Vlan100
2.2.2.2 1 Full/DROther 00:00:37 0 Vlan200
3.3.3.3 1 Full/BDR 00:00:31 0 Vlan100
3. Configure router priorities for interfaces:
# Set the router priority of VLAN-interface 100 to 100 on Switch A.
[SwitchA] interface Vlan-interface 100
[SwitchA-Vlan-interface100] ospfv3 dr-priority 100
[SwitchA-Vlan-interface100] quit
# Set the router priority of VLAN-interface 200 to 0 on Switch B.
[SwitchB] interface vlan-interface 200
[SwitchB-Vlan-interface200] ospfv3 dr-priority 0
[SwitchB-Vlan-interface200] quit
# Set the router priority of VLAN-interface 100 to 2 on Switch C.
[SwitchC] interface Vlan-interface 100
[SwitchC-Vlan-interface100] ospfv3 dr-priority 2
[SwitchC-Vlan-interface100] quit
# Display neighbor information on Switch A. Router priorities have been updated, but the DR and BDR are not changed.
[SwitchA] display ospfv3 peer
OSPFv3 Process 1 with Router ID 1.1.1.1
Area: 0.0.0.0
-------------------------------------------------------------------------
Router ID Pri State Dead-Time InstID Interface
2.2.2.2 0 2-Way/DROther 00:00:36 0 Vlan200
3.3.3.3 2 Full/BDR 00:00:35 0 Vlan200
4.4.4.4 1 Full/DR 00:00:33 0 Vlan200
# Display neighbor information on Switch D. Switch D is still the DR.
[SwitchD] display ospfv3 peer
OSPFv3 Process 1 with Router ID 4.4.4.4
Area: 0.0.0.0
-------------------------------------------------------------------------
Router ID Pri State Dead-Time InstID Interface
1.1.1.1 100 Full/DROther 00:00:30 0 Vlan100
2.2.2.2 0 Full/DROther 00:00:37 0 Vlan200
3.3.3.3 2 Full/BDR 00:00:31 0 Vlan100
4. Restart DR and BDR election:
# Use the shutdown and undo shutdown commands on interfaces to restart DR and BDR election. (Details not shown.)
# Display neighbor information on Switch A. The output shows that Switch C becomes the BDR.
[SwitchA] display ospfv3 peer
OSPFv3 Process 1 with Router ID 1.1.1.1
Area: 0.0.0.0
-------------------------------------------------------------------------
Router ID Pri State Dead-Time InstID Interface
2.2.2.2 0 Full/DROther 00:00:36 0 Vlan200
3.3.3.3 2 Full/BDR 00:00:35 0 Vlan100
4.4.4.4 1 Full/DROther 00:00:33 0 Vlan200
# Display neighbor information on Switch D.
[SwitchD] display ospfv3 peer
OSPFv3 Process 1 with Router ID 4.4.4.4
Area: 0.0.0.0
-------------------------------------------------------------------------
Router ID Pri State Dead-Time InstID Interface
1.1.1.1 100 Full/DR 00:00:30 0 Vlan100
2.2.2.2 0 2-Way/DROther 00:00:37 0 Vlan200
3.3.3.3 2 Full/BDR 00:00:31 0 Vlan100
The output shows that Switch A becomes the DR.
OSPFv3 route redistribution configuration example
Network requirements
As shown in Figure 99:
· Switch A, Switch B, and Switch C are in Area 2.
· OSPFv3 process 1 and OSPFv3 process 2 run on Switch B. Switch B communicates with Switch A and Switch C through OSPFv3 process 1 and OSPFv3 process 2.
· Configure OSPFv3 process 2 to redistribute direct routes and the routes from OSPFv3 process 1 on Switch B, and set the default metric for redistributed routes to 3. Switch C can then learn the routes destined for 1::0/64 and 2::0/64, and Switch A cannot learn the routes destined for 3::0/64 or 4::0/64.
Configuration procedure
1. Configure IPv6 addresses for interfaces. (Details not shown.)
2. Configure basic OSPFv3:
# Enable OSPFv3 process 1 on Switch A.
<SwitchA> system-view
[SwitchA] ospfv3 1
[SwitchA-ospfv3-1] router-id 1.1.1.1
[SwitchA-ospfv3-1] quit
[SwitchA] interface vlan-interface 100
[SwitchA-Vlan-interface100] ospfv3 1 area 2
[SwitchA-Vlan-interface100] quit
[SwitchA] interface vlan-interface 200
[SwitchA-Vlan-interface200] ospfv3 1 area 2
[SwitchA-Vlan-interface200] quit
# Enable OSPFv3 process 1 and OSPFv3 process 2 on Switch B.
<SwitchB> system-view
[SwitchB] ospfv3 1
[SwitchB-ospfv3-1] router-id 2.2.2.2
[SwitchB-ospfv3-1] quit
[SwitchB] interface vlan-interface 100
[SwitchB-Vlan-interface100] ospfv3 1 area 2
[SwitchB-Vlan-interface100] quit
[SwitchB] ospfv3 2
[SwitchB-ospfv3-2] router-id 3.3.3.3
[SwitchB-ospfv3-2] quit
[SwitchB] interface vlan-interface 300
[SwitchB-Vlan-interface300] ospfv3 2 area 2
[SwitchB-Vlan-interface300] quit
# Enable OSPFv3 process 2 on Switch C.
<SwitchC> system-view
[SwitchC] ospfv3 2
[SwitchC-ospfv3-2] router-id 4.4.4.4
[SwitchC-ospfv3-2] quit
[SwitchC] interface vlan-interface 300
[SwitchC-Vlan-interface300] ospfv3 2 area 2
[SwitchC-Vlan-interface300] quit
[SwitchC] interface vlan-interface 400
[SwitchC-Vlan-interface400] ospfv3 2 area 2
[SwitchC-Vlan-interface400] quit
# Display the routing table on Switch C.
[SwitchC] display ipv6 routing-table
Destinations : 7 Routes : 7
Destination: ::1/128 Protocol : Direct
NextHop : ::1 Preference: 0
Interface : InLoop0 Cost : 0
Destination: 3::/64 Protocol : Direct
NextHop : :: Preference: 0
Interface : Vlan300 Cost : 0
Destination: 3::2/128 Protocol : Direct
NextHop : ::1 Preference: 0
Interface : InLoop0 Cost : 0
Destination: 4::/64 Protocol : Direct
NextHop : :: Preference: 0
Interface : Vlan400 Cost : 0
Destination: 4::1/128 Protocol : Direct
NextHop : ::1 Preference: 0
Interface : InLoop0 Cost : 0
Destination: FE80::/10 Protocol : Direct
NextHop : :: Preference: 0
Interface : NULL0 Cost : 0
Destination: FF00::/8 Protocol : Direct
NextHop : :: Preference: 0
Interface : NULL0
3. Configure OSPFv3 route redistribution:
# Configure OSPFv3 process 2 to redistribute direct routes and the routes from OSPFv3 process 1 on Switch B.
[SwitchB] ospfv3 2
[SwitchB-ospfv3-2] default cost 3
[SwitchB-ospfv3-2] import-route ospfv3 1
[SwitchB-ospfv3-2] import-route direct
[SwitchB-ospfv3-2] quit
# Display the routing table on Switch C.
[SwitchC] display ipv6 routing-table
Destinations : 9 Routes : 9
Destination: ::1/128 Protocol : Direct
NextHop : ::1 Preference: 0
Interface : InLoop0 Cost : 0
Destination: 1::/64 Protocol : O_ASE2
NextHop : FE80::200:CFF:FE01:1C03 Preference: 150
Interface : Vlan300 Cost : 3
Destination: 2::/64 Protocol : O_ASE2
NextHop : FE80::200:CFF:FE01:1C03 Preference: 150
Interface : Vlan300 Cost : 3
Destination: 3::/64 Protocol : Direct
NextHop : :: Preference: 0
Interface : Vlan300 Cost : 0
Destination: 3::2/128 Protocol : Direct
NextHop : ::1 Preference: 0
Interface : InLoop0 Cost : 0
Destination: 4::/64 Protocol : Direct
NextHop : :: Preference: 0
Interface : Vlan400 Cost : 0
Destination: 4::1/128 Protocol : Direct
NextHop : ::1 Preference: 0
Interface : InLoop0 Cost : 0
Destination: FE80::/10 Protocol : Direct
NextHop : :: Preference: 0
Interface : NULL0 Cost : 0
Destination: FF00::/8 Protocol : Direct
NextHop : :: Preference: 0
Interface : NULL0
OSPFv3 route summarization configuration example
Network requirements
As shown in Figure 100:
· Switch A, Switch B, and Switch C are in Area 2.
· OSPFv3 process 1 and OSPFv3 process 2 run on Switch B. Switch B communicates with Switch A and Switch C through OSPFv3 process 1 and OSPFv3 process 2, respectively.
· On Switch A, configure IPv6 addresses 2:1:1::1/64, 2:1:2::1/64, and 2:1:3::1/64 for VLAN-interface 200.
· On Switch B, configure OSPFv3 process 2 to redistribute direct routes and the routes from OSPFv3 process 1. Switch C can then learn the routes destined for 2::/64, 2:1:1::/64, 2:1:2::/64, and 2:1:3::/64.
· On Switch B, configure route summarization to advertise only summary route 2::/16 to Switch C.
Configuration procedure
1. Configure IPv6 addresses for interfaces. (Details not shown.)
2. Configure OSPFv3:
# Enable OSPFv3 process 1 on Switch A.
<SwitchA> system-view
[SwitchA] ospfv3 1
[SwitchA-ospfv3-1] router-id 1.1.1.1
[SwitchA-ospfv3-1] quit
[SwitchA] interface vlan-interface 100
[SwitchA-Vlan-interface100] ospfv3 1 area 2
[SwitchA-Vlan-interface100] quit
[SwitchA] interface vlan-interface 200
[SwitchA-Vlan-interface200] ipv6 address 2:1:1::1 64
[SwitchA-Vlan-interface200] ipv6 address 2:1:2::1 64
[SwitchA-Vlan-interface200] ipv6 address 2:1:3::1 64
[SwitchA-Vlan-interface200] ospfv3 1 area 2
[SwitchA-Vlan-interface200] quit
# Enable OSPFv3 process 1 and OSPFv3 process 2 on Switch B.
<SwitchB> system-view
[SwitchB] ospfv3 1
[SwitchB-ospfv3-1] router-id 2.2.2.2
[SwitchB-ospfv3-1] quit
[SwitchB] interface vlan-interface 100
[SwitchB-Vlan-interface100] ospfv3 1 area 2
[SwitchB-Vlan-interface100] quit
[SwitchB] ospfv3 2
[SwitchB-ospfv3-2] router-id 3.3.3.3
[SwitchB-ospfv3-2] quit
[SwitchB] interface vlan-interface 300
[SwitchB-Vlan-interface300] ospfv3 2 area 2
[SwitchB-Vlan-interface300] quit
# Enable OSPFv3 process 2 on Switch C.
<SwitchC> system-view
[SwitchC] ospfv3 2
[SwitchC-ospfv3-2] router-id 4.4.4.4
[SwitchC-ospfv3-2] quit
[SwitchC] interface vlan-interface 300
[SwitchC-Vlan-interface300] ospfv3 2 area 2
[SwitchC-Vlan-interface300] quit
[SwitchC] interface vlan-interface 400
[SwitchC-Vlan-interface400] ospfv3 2 area 2
[SwitchC-Vlan-interface400] quit
3. Configure OSPFv3 route redistribution:
# Configure OSPFv3 process 2 to redistribute direct routes and the routes from OSPFv3 process 1 on Switch B.
[SwitchB] ospfv3 2
[SwitchB-ospfv3-2] import-route ospfv3 1
[SwitchB-ospfv3-2] import-route direct
[SwitchB-ospfv3-2] quit
# Display the routing table on Switch C.
[SwitchC] display ipv6 routing-table
Destinations : 12 Routes : 12
Destination: ::1/128 Protocol : Direct
NextHop : ::1 Preference: 0
Interface : InLoop0 Cost : 0
Destination: 1::/64 Protocol : O_ASE2
NextHop : FE80::200:CFF:FE01:1C03 Preference: 150
Interface : Vlan300 Cost : 1
Destination: 2::/64 Protocol : O_ASE2
NextHop : FE80::200:CFF:FE01:1C03 Preference: 150
Interface : Vlan300 Cost : 1
Destination: 2:1:1::/64 Protocol : O_ASE2
NextHop : FE80::200:CFF:FE01:1C03 Preference: 150
Interface : Vlan300 Cost : 1
Destination: 2:1:2::/64 Protocol : O_ASE2
NextHop : FE80::200:CFF:FE01:1C03 Preference: 150
Interface : Vlan300 Cost : 1
Destination: 2:1:3::/64 Protocol : O_ASE2
NextHop : FE80::200:CFF:FE01:1C03 Preference: 150
Interface : Vlan300 Cost : 1
Destination: 3::/64 Protocol : Direct
NextHop : 3::2 Preference: 0
Interface : Vlan300 Cost : 0
Destination: 3::2/128 Protocol : Direct
NextHop : ::1 Preference: 0
Interface : InLoop0 Cost : 0
Destination: 4::/64 Protocol : Direct
NextHop : 4::1 Preference: 0
Interface : Vlan400 Cost : 0
Destination: 4::1/128 Protocol : Direct
NextHop : ::1 Preference: 0
Interface : InLoop0 Cost : 0
Destination: FE80::/10 Protocol : Direct
NextHop : :: Preference: 0
Interface : NULL0 Cost : 0
Destination: FF00::/8 Protocol : Direct
NextHop : :: Preference: 0
Interface : NULL0
4. Configure ASBR route summarization:
# On Switch B, configure OSPFv3 process 2 to advertise a single route 2::/16.
[SwitchB] ospfv3 2
[SwitchB-ospfv3-2] asbr-summary 2:: 16
[SwitchB-ospfv3-2] quit
# Display the routing table on Switch C.
[SwitchC] display ipv6 routing-table
Destinations : 9 Routes : 9
Destination: ::1/128 Protocol : Direct
NextHop : ::1 Preference: 0
Interface : InLoop0 Cost : 0
Destination: 1::/64 Protocol : O_ASE2
NextHop : FE80::200:CFF:FE01:1C03 Preference: 150
Interface : Vlan300 Cost : 1
Destination: 2::/16 Protocol : O_ASE2
NextHop : FE80::200:CFF:FE01:1C03 Preference: 150
Interface : Vlan300 Cost : 1
Destination: 3::/64 Protocol : Direct
NextHop : 3::2 Preference: 0
Interface : Vlan300 Cost : 0
Destination: 3::2/128 Protocol : Direct
NextHop : ::1 Preference: 0
Interface : InLoop0 Cost : 0
Destination: 4::/64 Protocol : Direct
NextHop : 4::1 Preference: 0
Interface : Vlan400 Cost : 0
Destination: 4::1/128 Protocol : Direct
NextHop : ::1 Preference: 0
Interface : InLoop0 Cost : 0
Destination: FE80::/10 Protocol : Direct
NextHop : :: Preference: 0
Interface : NULL0 Cost : 0
Destination: FF00::/8 Protocol : Direct
NextHop : :: Preference: 0
Interface : NULL0
OSPFv3 GR configuration example
Network requirements
As shown in Figure 101:
· Switch A, Switch B, and Switch C that reside in the same AS and the same OSPFv3 routing domain are GR capable.
· Switch A acts as the GR restarter. Switch B and Switch C act as the GR helpers, and synchronize their LSDBs with Switch A through GR.
Configuration procedure
1. Configure IPv6 addresses for interfaces. (Details not shown.)
2. Configure basic OSPFv3:
# On Switch A, enable OSPFv3 process 1, enable GR, and set the router ID to 1.1.1.1.
<SwitchA> system-view
[SwitchA] ospfv3 1
[SwitchA-ospfv3-1] router-id 1.1.1.1
[SwitchA-ospfv3-1] graceful-restart enable
[SwitchA-ospfv3-1] quit
[SwitchA] interface vlan-interface 100
[SwitchA-Vlan-interface100] ospfv3 1 area 1
[SwitchA-Vlan-interface100] quit
# On Switch B, enable OSPFv3 and set the router ID to 2.2.2.2. (By default, GR helper is enabled on Switch B.)
<SwitchB> system-view
[SwitchB] ospfv3 1
[SwitchB-ospfv3-1] router-id 2.2.2.2
[SwitchB-ospfv3-1] quit
[SwitchB] interface vlan-interface 100
[SwitchB-Vlan-interface100] ospfv3 1 area 1
[SwitchB-Vlan-interface100] quit
# On Switch C, enable OSPFv3 and set the router ID to 3.3.3.3. (By default, GR helper is enabled on Switch C.)
<SwitchC> system-view
[SwitchC] ospfv3 1
[SwitchC-ospfv3-1] router-id 3.3.3.3
[SwitchC-ospfv3-1] quit
[SwitchC] interface vlan-interface 100
[SwitchC-Vlan-interface100] ospfv3 1 area 1
[SwitchC-Vlan-interface100] quit
Verifying the configuration
# Perform a master/backup switchover on Switch A to trigger an OSPFv3 GR operation. (Details not shown.)
OSPFv3 NSR configuration example
Network requirements
As shown in Figure 102, Switch S, Switch A, and Switch B belong to the same AS and OSPFv3 routing domain. Enable OSPFv3 NSR on Switch S to ensure correct routing when an active/standby switchover occurs on Switch S.
Configuration procedure
1. Configure IP addresses and subnet masks for interfaces on the switches. (Details not shown.)
2. Configure OSPFv3 on the switches to ensure that Switch S, Switch A, and Switch B can communicate with each other at Layer 3. (Details not shown.)
3. Configure OSPFv3:
# On Switch A, enable OSPFv3, and set the router ID to 1.1.1.1.
<SwitchA> system-view
[SwitchA] ospfv3 1
[SwitchA-ospfv3-1] router-id 1.1.1.1
[SwitchA-ospfv3-1] quit
[SwitchA] interface vlan-interface 100
[SwitchA-Vlan-interface100] ospfv3 1 area 1
[SwitchA-Vlan-interface100] quit
# On Switch B, enable OSPFv3, and set the router ID to 2.2.2.2.
<SwitchB> system-view
[SwitchB] ospfv3 1
[SwitchB-ospfv3-1] router-id 2.2.2.2
[SwitchB-ospfv3-1] quit
[SwitchB] interface vlan-interface 200
[SwitchB-Vlan-interface200] ospfv3 1 area 1
[SwitchB-Vlan-interface200] quit
# On Switch S, enable OSPFv3, set the router ID to 3.3.3.3, and enable NSR.
<SwitchS> system-view
[SwitchS] ospfv3 1
[SwitchS-ospfv3-1] router-id 3.3.3.3
[SwitchS-ospfv3-1] non-stop-routing
[SwitchS-ospfv3-1] quit
[SwitchS] interface vlan-interface 100
[SwitchS-Vlan-interface100] ospfv3 1 area 1
[SwitchS-Vlan-interface100] quit
[SwitchS] interface vlan-interface 200
[SwitchS-Vlan-interface200] ospfv3 1 area 1
[SwitchS-Vlan-interface200] quit
Verifying the configuration
# Verify the following:
· When an active/standby switchover occurs on Switch S, the neighbor relationships and routing information on Switch A and Switch B have not changed. (Details not shown.)
· The traffic from Switch A to Switch B has not been impacted. (Details not shown.)
BFD for OSPFv3 configuration example
Network requirements
As shown in Figure 103:
· Configure OSPFv3 on Switch A, Switch B and Switch C and configure BFD over the link Switch A<—>L2 Switch<—>Switch B.
· After the link Switch A<—>L2 Switch<—>Switch B fails, BFD can quickly detect the failure and notify OSPFv3 of the failure. Then Switch A and Switch B communicate through Switch C.
Table 25 Interface and IP address assignment
Device |
Interface |
IPv6 address |
Switch A |
Vlan-int10 |
2001::1/64 |
Switch A |
Vlan-int11 |
2001:2::1/64 |
Switch B |
Vlan-int10 |
2001::2/64 |
Switch B |
Vlan-int13 |
2001:3::2/64 |
Switch C |
Vlan-int11 |
2001:2::2/64 |
Switch C |
Vlan-int13 |
2001:3::1/64 |
Configuration procedure
1. Configure IPv6 addresses for the interfaces. (Details not shown.)
2. Configure basic OSPFv3:
# On Switch A, enable OSPFv3 and specify the router ID as 1.1.1.1.
<SwitchA> system-view
[SwitchA] ospfv3
[SwitchA-ospfv3-1] router-id 1.1.1.1
[SwitchA-ospfv3-1] quit
[SwitchA] interface vlan-interface 10
[SwitchA-Vlan-interface10] ospfv3 1 area 0
[SwitchA-Vlan-interface10] quit
[SwitchA] interface vlan-interface 11
[SwitchA-Vlan-interface11] ospfv3 1 area 0
[SwitchA-Vlan-interface11] quit
# On Switch B, enable OSPFv3 and specify the router ID as 2.2.2.2.
<SwitchB> system-view
[SwitchB] ospfv3
[SwitchB-ospfv3-1] router-id 2.2.2.2
[SwitchB-ospfv3-1] quit
[SwitchB] interface vlan-interface 10
[SwitchB-Vlan-interface10] ospfv3 1 area 0
[SwitchB-Vlan-interface10] quit
[SwitchB] interface vlan-interface 13
[SwitchB-Vlan-interface13] ospfv3 1 area 0
[SwitchB-Vlan-interface13] quit
# On Switch C, enable OSPFv3 and specify the router ID as 3.3.3.3.
<SwitchC> system-view
[SwitchC] ospfv3
[SwitchC-ospfv3-1] router-id 3.3.3.3
[SwitchC-ospfv3-1] quit
[SwitchC] interface vlan-interface 11
[SwitchC-Vlan-interface11] ospfv3 1 area 0
[SwitchC-Vlan-interface11] quit
[SwitchC] interface vlan-interface 13
[SwitchC-Vlan-interface13] ospfv3 1 area 0
[SwitchC-Vlan-interface13] quit
3. Configure BFD:
# Enable BFD and configure BFD parameters on Switch A.
[SwitchA] bfd session init-mode active
[SwitchA] interface vlan-interface 10
[SwitchA-Vlan-interface10] ospfv3 bfd enable
[SwitchA-Vlan-interface10] bfd min-transmit-interval 500
[SwitchA-Vlan-interface10] bfd min-receive-interval 500
[SwitchA-Vlan-interface10] bfd detect-multiplier 7
[SwitchA-Vlan-interface10] return
# Enable BFD and configure BFD parameters on Switch B.
[SwitchB] bfd session init-mode active
[SwitchB] interface vlan-interface 10
[SwitchB-Vlan-interface10] ospfv3 bfd enable
[SwitchB-Vlan-interface10] bfd min-transmit-interval 500
[SwitchB-Vlan-interface10] bfd min-receive-interval 500
[SwitchB-Vlan-interface10] bfd detect-multiplier 6
Verifying the configuration
# Display the BFD information on Switch A.
<SwitchA> display bfd session
Total Session Num: 1 Init Mode: Active
IPv6 Session Working Under Ctrl Mode:
Local Discr: 1441 Remote Discr: 1450
Source IP: FE80::20F:FF:FE00:1202 (link-local address of VLAN-interface 10 on Switch A)
Destination IP: FE80::20F:FF:FE00:1200 (link-local address of VLAN-interface 10 on Switch B)
Session State: Up Interface: Vlan10
Hold Time: 2319ms
# Display routes destined for 2001:4::0/64 on Switch A.
<SwitchA> display ipv6 routing-table 2001:4::0 64
Summary Count : 1
Destination: 2001:4::/64 Protocol : O_INTRA
NextHop : FE80::20F:FF:FE00:1200 Preference: 10
Interface : Vlan10 Cost : 1
The output information shows that Switch A communicates with Switch B through VLAN-interface 10. The link over VLAN-interface 10 fails.
# Display routes to 2001:4::0/64 on Switch A.
<SwitchA> display ipv6 routing-table 2001:4::0 64
Summary Count : 1
Destination: 2001:4::/64 Protocol : O_INTRA
NextHop : FE80::BAAF:67FF:FE27:DCD0 Preference: 10
Interface : Vlan11 Cost : 2
The output shows that Switch A communicates with Switch B through VLAN-interface 11.
OSPFv3 FRR configuration example
Network requirements
As shown in Figure 104, Switch A, Switch B, and Switch C reside in the same OSPFv3 domain. Configure OSPFv3 FRR so that when Link A fails, traffic is immediately switched to Link B.
Table 26 Interface and IP address assignment
Device |
Interface |
IP address |
Device |
Interface |
IP address |
Switch A |
Vlan-int100 |
1::1/64 |
Switch B |
Vlan-int101 |
3::1/64 |
|
Vlan-int200 |
2::1/64 |
|
Vlan-int200 |
2::2/64 |
|
Loop0 |
10::1/128 |
|
Loop0 |
20::1/128 |
Switch C |
Vlan-int100 |
1::2/64 |
|
|
|
|
Vlan-int101 |
3::2/64 |
|
|
|
Configuration procedure
1. Configure IPv6 addresses and subnet masks for interfaces on the switches. (Details not shown.)
2. Configure OSPFv3 on the switches to ensure that Switch A, Switch B, and Switch C can communicate with each other at the network layer. (Details not shown.)
3. Configure OSPFv3 FRR to automatically calculate the backup next hop:
You can enable OSPFv3 FRR to either calculate a backup next hop by using the LFA algorithm, or specify a backup next hop by using a routing policy.
? (Method 1.) Enable OSPFv3 FRR to calculate the backup next hop by using the LFA algorithm:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] ospfv3 1
[SwitchA-ospfv3-1] fast-reroute lfa
[SwitchA-ospfv3-1] quit
# Configure Switch B.
<SwitchB> system-view
[SwitchB] ospfv3 1
[SwitchB-ospfv3-1] fast-reroute lfa
[SwitchB-ospfv3-1] quit
? (Method 2.) Enable OSPFv3 FRR to designate a backup next hop by using a routing policy:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] ipv6 prefix-list abc index 10 permit 10:: 128
[SwitchA] route-policy frr permit node 10
[SwitchA-route-policy-frr-10] if-match ipv6 address prefix-list abc
[SwitchA-route-policy-frr-10] apply ipv6 fast-reroute backup-interface vlan-interface 100 backup-nexthop 1::2/64
[SwitchA-route-policy-frr-10] quit
[SwitchA] ospfv3 1
[SwitchA-ospfv3-1] fast-reroute route-policy frr
[SwitchA-ospfv3-1] quit
# Configure Switch B.
<SwitchB> system-view
[SwitchB] ipv6 prefix-list abc index 10 permit 20:: 128
[SwitchB] route-policy frr permit node 10
[SwitchB-route-policy-frr-10] if-match ipv6 address prefix-list abc
[SwitchB-route-policy-frr-10] apply ipv6 fast-reroute backup-interface vlan-interface 101 backup-nexthop 3::2/64
[SwitchB-route-policy-frr-10] quit
[SwitchB] ospfv3 1
[SwitchB-ospfv3-1] fast-reroute route-policy frr
[SwitchB-ospfv3-1] quit
Verifying the configuration
# Display the route 20::1/128 on Switch A to view the backup next hop information.
[SwitchA] display ipv6 routing-table 20::1 128 verbose
Summary count : 1
Destination: 20::1/128
Protocol: O_INTRA
Process ID: 1
SubProtID: 0x1 Age: 00h03m45s
Cost: 6 Preference: 10
IpPre: N/A QosLocalID: N/A
Tag: 0 State: Active Adv
OrigTblID: 0x0 OrigVrf: default-vrf
TableID: 0xa OrigAs: 0
NibID: 0x23000005 LastAs: 0
AttrID: 0xffffffff Neighbor: ::
Flags: 0x10041 OrigNextHop: FE80::7685:45FF:FEAD:102
Label: NULL RealNextHop: FE80::7685:45FF:FEAD:102
BkLabel: NULL BkNextHop: FE80::34CD:9FF:FE2F:D02
Tunnel ID: Invalid Interface: Vlan-interface200
BkTunnel ID: Invalid BkInterface: Vlan-interface100
FtnIndex: 0x0 TrafficIndex: N/A
Connector: N/A
# Display the route 10::1/128 on Switch B to view the backup next hop information.
[SwitchB] display ipv6 routing-table 10::1 128 verbose
Summary count : 1
Destination: 10::1/128
Protocol: O_INTRA
Process ID: 1
SubProtID: 0x1 Age: 00h03m10s
Cost: 1 Preference: 10
IpPre: N/A QosLocalID: N/A
Tag: 0 State: Active Adv
OrigTblID: 0x0 OrigVrf: default-vrf
TableID: 0xa OrigAs: 0
NibID: 0x23000006 LastAs: 0
AttrID: 0xffffffff Neighbor: ::
Flags: 0x10041 OrigNextHop: FE80::34CC:E8FF:FE5B:C02
Label: NULL RealNextHop: FE80::34CC:E8FF:FE5B:C02
BkLabel: NULL BkNextHop: FE80::7685:45FF:FEAD:102
Tunnel ID: Invalid Interface: Vlan-interface200
BkTunnel ID: Invalid BkInterface: Vlan-interface101
FtnIndex: 0x0 TrafficIndex: N/A
Connector: N/A
Configuring IPv6 IS-IS
Overview
IPv6 IS-IS supports all IPv4 IS-IS features except that it advertises IPv6 routing information. This chapter describes only IPv6 IS-IS specific configuration tasks. For information about IS-IS, see "Configuring IS-IS."
Intermediate System-to-Intermediate System (IS-IS) supports multiple network protocols, including IPv6. To support IPv6, the IETF added two type-length-values (TLVs) and a new network layer protocol identifier (NLPID).
The TLVs are as follows:
· IPv6 Reachability—Contains routing prefix and metric information to describe network reachability and has a type value of 236 (0xEC).
· IPv6 Interface Address—Same as the "IP Interface Address" TLV in IPv4 ISIS, except that the 32-bit IPv4 address is translated to the 128-bit IPv6 address.
The new NLPID is an 8-bit field that identifies which network layer protocol is supported. For IPv6, the NLPID is 142 (0x8E), which must be carried in hello packets sent by IPv6 IS-IS.
Configuring basic IPv6 IS-IS
Before you configure basic IPv6 IS-IS, complete the following tasks:
· Configure IPv6 addresses for interfaces to ensure IPv6 connectivity between neighboring nodes.
· Enable IS-IS.
Basic IPv6 IS-IS configuration can implement the interconnection of IPv6 networks.
To configure basic IPv6 IS-IS:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enable an IS-IS process and enter IS-IS view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
By default, no IS-IS process is enabled. |
3. Configure the network entity title (NET) for the IS-IS process. |
network-entity net |
By default, no NET is configured. |
4. Create the IPv6 address family and enter its view. |
address-family ipv6 [ unicast ] |
By default, no IS-IS IPv6 address family exists. |
5. Return to IS-IS view. |
quit |
N/A |
6. Return to system view. |
quit |
N/A |
7. Enter interface view. |
interface interface-type interface-number |
N/A |
8. Enable IPv6 for IS-IS on the interface. |
isis ipv6 enable [ process-id ] |
By default, IPv6 is disabled for IS-IS on an interface. |
Configuring IPv6 IS-IS route control
Before you configure IPv6 IS-IS route control, complete basic IPv6 IS-IS configuration.
To configure IPv6 IS-IS route control:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Enter IS-IS IPv6 address family view. |
address-family ipv6 [ unicast ] |
N/A |
4. Specify a preference for IPv6 IS-IS routes. |
preference { route-policy route-policy-name | preference } * |
By default, the default setting is 15. |
5. Configure an IPv6 IS-IS summary route. |
summary ipv6-prefix prefix-length [ avoid-feedback | generate_null0_route | [ level-1 | level-1-2 | level-2 ] | tag tag ] * |
By default, no IPv6 IS-IS summary route is configured. |
6. Configure IPv6 IS-IS to advertise a default route. |
default-route-advertise [ avoid-learning | [ level-1 | level-1-2 | level-2 ] | route-policy route-policy-name | tag tag ] * |
By default, IPv6 IS-IS does not advertise Level-1 and Level-2 default routes. |
7. Configure IPv6 IS-IS to filter redistributed routes. |
filter-policy { ipv6-acl-number | prefix-list prefix-list-name | route-policy route-policy-name } export [ protocol [ process-id ] ] |
By default, IPv6 IS-IS does not filter redistributed routes. This command is usually used together with the import-route command. |
8. Configure IPv6 IS-IS to filter received routes. |
filter-policy { ipv6-acl-number | prefix-list prefix-list-name | route-policy route-policy-name } import |
By default, IPv6 IS-IS does not filter received routes. |
9. Configure IPv6 IS-IS to redistribute routes from another routing protocol. |
import-route protocol [ as-number | process-id ] [ allow-ibgp ] [ allow-direct | cost cost-value | [ level-1 | level-1-2 | level-2 ] | route-policy route-policy-name | tag tag ] * |
By default, IPv6 IS-IS does not redistribute routes from any other routing protocol. |
10. Configure the maximum number of redistributed Level 1/Level 2 IPv6 routes. |
import-route limit number |
By default, the maximum number of redistributed Level 1/Level 2 IPv6 routes is not configured. |
11. Configure route advertisement from Level-2 to Level-1. |
import-route isisv6 level-2 into level-1 [ filter-policy { ipv6-acl-number | prefix-list prefix-list-name | route-policy route-policy-name } | tag tag ] * |
By default, IPv6 IS-IS does not advertise routes from Level-2 to Level-1. |
12. Configure route advertisement from Level-1 to Level-2. |
import-route isisv6 level-1 into level-2 [ filter-policy { ipv6-acl-number | prefix-list prefix-list-name | route-policy route-policy-name } | tag tag ] * |
By default, IPv6 IS-IS advertises routes from Level-1 to Level-2. |
13. Specify the maximum number of ECMP routes for load balancing. |
maximum load-balancing number |
By default, the maximum number of ECMP routes equals the maximum number of ECMP routes supported by the system. |
Configuring IPv6 IS-IS link cost
Configuring an IPv6 IS-IS cost for an interface
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Specify an IS-IS cost style. |
cost-style { narrow | wide | wide-compatible | { compatible | narrow-compatible } [ relax-spf-limit ] } |
By default, the IS-IS cost type is narrow. |
4. Enter IPv6 address family view. |
address-family ipv6 [ unicast ] |
N/A |
5. Enable IPv6 IS-IS MTR. |
multi-topology [ compatible ] |
By default, IPv6 IS-IS MTR is disabled. |
6. Return to IS-IS view. |
quit |
N/A |
7. Return to system view. |
quit |
N/A |
8. Enter interface view. |
interface interface-type interface-number |
N/A |
9. Enable IPv6 for IS-IS on the interface. |
isis ipv6 enable [ process-id ] |
By default, IPv6 is disabled for IS-IS on an interface. |
10. Specify an IPv6 cost for the IS-IS interface. |
isis ipv6 cost |
By default, no IPv6 cost is specified for the interface. |
Configuring a global IPv6 IS-IS cost
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Specify an IS-IS cost style. |
cost-style { wide | wide-compatible | compatible } |
By default, the IS-IS cost style is narrow. |
4. Enter IPv6 address family view. |
address-family ipv6 [ unicast ] |
N/A |
5. Enable IPv6 IS-IS MTR. |
multi-topology [ compatible ] |
By default, IPv6 IS-IS MTR is disabled. |
6. Specify a global IPv6 IS-IS cost. |
circuit-cost cost-value [ level-1 | level-2 ] |
By default, no global IPv6 cost is specified. |
Enabling automatic link cost calculation
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Specify an IS-IS cost style. |
cost-style { wide | wide-compatible } |
By default, the IS-IS cost style is narrow. |
4. Enter IPv6 address family view. |
address-family ipv6 [ unicast ] |
N/A |
5. Enable IPv6 IS-IS MTR. |
multi-topology [ compatible ] |
By default, IPv6 IS-IS MTR is disabled. |
6. Enable automatic IPv6 IS-IS cost calculation. |
auto-cost enable |
By default, automatic IPv6 IS-IS cost calculation is disabled. |
7. (Optional.) Configure a bandwidth reference value for automatic IPv6 IS-IS cost calculation. |
bandwidth-reference value |
The default setting is 100 Mbps. |
Tuning and optimizing IPv6 IS-IS networks
Configuration prerequisites
Before you tune and optimize IPv6 IS-IS networks, complete basic IPv6 IS-IS tasks.
Assigning a convergence priority to IPv6 IS-IS routes
A topology change causes IS-IS routing convergence. To improve convergence speed, you can assign convergence priorities to IPv6 IS-IS routes. Convergence priority levels are critical, high, medium, and low. The higher the convergence priority, the faster the convergence speed.
By default, IPv6 IS-IS host routes have medium convergence priority, and other IPv6 IS-IS routes have low convergence priority.
To assign a convergence priority to specific IPv6 IS-IS routes:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Specify an IS-IS cost style. |
cost-style { wide | wide-compatible | compatible } |
By default, the IS-IS cost style is narrow. |
4. Enter IPv6 address family view. |
address-family ipv6 [ unicast ] |
N/A |
5. Enable IPv6 IS-IS MTR. |
multi-topology [ compatible ] |
By default, IPv6 IS-IS MTR is disabled. |
6. Assign a convergence priority to specific IPv6 IS-IS routes. |
·
Method 1: ·
Method 2: |
By default, IPv6 IS-IS routes, except IPv6 IS-IS host routes, have the low convergence priority. |
Setting the LSDB overload bit
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Specify an IS-IS cost style. |
cost-style { wide | wide-compatible | compatible } |
By default, the IS-IS cost style is narrow. |
4. Enter IPv6 address family view. |
address-family ipv6 [ unicast ] |
N/A |
5. Enable IPv6 IS-IS MTR. |
multi-topology [ compatible ] |
By default, IPv6 IS-IS MTR is disabled. |
6. Set the overload bit. |
set-overload [ on-startup [ [ start-from-nbr system-id [ timeout1 [ nbr-timeout ] ] ] | timeout2 | wait-for-bgp4+ [ timeout3 ] ] ] [ allow { external | interlevel } * ] |
By default, the overload bit is not set. |
Configuring a tag value on an interface
When IS-IS advertises an IPv6 prefix with a tag value, it adds the tag to the IPv6 reachability information TLV, regardless of the link cost style.
To configure a tag value on an interface:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Configure a tag value on the interface. |
isis ipv6 tag tag |
By default, no tag value is configured on an interface. |
Controlling SPF calculation interval
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Specify an IS-IS cost style. |
cost-style { wide | wide-compatible | compatible } |
By default, the IS-IS cost style is narrow. |
4. Enter IPv6 address family view. |
address-family ipv6 [ unicast ] |
N/A |
5. Enable IPv6 IS-IS MTR. |
multi-topology [ compatible ] |
By default, IPv6 IS-IS MTR is disabled. |
6. Set the SPF calculation interval. |
timer spf maximum-interval [ minimum-interval [ incremental-interval ] ] |
By default: · The maximum interval is 5 seconds. · The minimum interval is 50 milliseconds. · The incremental interval is 200 milliseconds. |
Enabling IPv6 IS-IS ISPF
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Specify an IS-IS cost style. |
cost-style { wide | wide-compatible | compatible } |
By default, the IS-IS cost style is narrow. |
4. Enter IPv6 address family view. |
address-family ipv6 [ unicast ] |
N/A |
5. Enable IPv6 IS-IS MTR. |
multi-topology [ compatible ] |
By default, IPv6 IS-IS MTR is disabled. |
6. Enable IPv6 IS-IS ISPF. |
ispf enable |
By default, IPv6 IS-IS ISPF is enabled. |
Enabling prefix suppression
Perform this task to disable an interface from advertising its prefix in LSPs. This enhances network security by preventing IP routing to the interval nodes and speeds up network convergence.
To enable prefix suppression:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Enable prefix suppression on the interface. |
isis ipv6 prefix-suppression |
By default, prefix suppression is disabled on an interface. |
Configuring BFD for IPv6 IS-IS
Bidirectional forwarding detection (BFD) can quickly detect faults between IPv6 IS-IS neighbors to improve the convergence speed of IPv6 IS-IS. For more information about BFD, see High Availability Configuration Guide.
To configure BFD for IPv6 IS-IS:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enable an IS-IS process and enter IS-IS view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Configure the NET for the IS-IS process. |
network-entity net |
By default, no NET is configured. |
4. Enter IPv6 address family view. |
address-family ipv6 [ unicast ] |
N/A |
5. Return to system view. |
quit |
N/A |
6. Enter interface view. |
interface interface-type interface-number |
N/A |
7. Enable IPv6 for IS-IS on the interface. |
isis ipv6 enable [ process-id ] |
By default, IPv6 is disabled for IS-IS on an interface. |
8. Enable BFD for IPv6 IS-IS. |
isis ipv6 bfd enable |
By default, BFD for IPv6 IS-IS is disabled. |
Configuring IPv6 IS-IS FRR
|
IMPORTANT: ECMP routes do not support FRR. |
A link or router failure on a path can cause packet loss and routing loop. IPv6 IS-IS FRR enables fast rerouting to minimize the failover time.
Figure 105 Network diagram for IPv6 IS-IS FRR
In Figure 105, after you enable FRR on Router B, IPv6 IS-IS FRR automatically calculates or designates a backup next hop when a link failure is detected. In this way, packets are directed to the backup next hop to reduce traffic recovery time. Meanwhile, IPv6 IS-IS calculates the shortest path based on the new network topology, and forwards packets over the path after network convergence.
You can assign a backup next hop for IPv6 IS-IS FRR in the following ways:
· Enable IPv6 IS-IS FRR to calculate a backup next hop through Loop Free Alternate (LFA) calculation.
· Designate a backup next hop with a routing policy for routes matching specific criteria.
Configuration prerequisites
Before you configure IPv6 IS-IS FRR, complete the following tasks:
· Configure IPv6 addresses for interfaces to ensure IP connectivity between neighboring nodes.
· Enable IPv6 IS-IS.
· Make sure the backup next hop is reachable.
Configuration procedure
Configuring IPv6 IS-IS FRR to calculate a backup next hop through LFA calculation
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. (Optional.) Disable LFA calculation on the interface. |
isis ipv6 fast-reroute lfa-backup exclude |
By default, the interface participates in LFA calculation and can be elected as a backup interface. |
4. Return to system view. |
quit |
N/A |
5. Enter IS-IS IPv6 unicast address family view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] address-family ipv6 [ unicast ] |
N/A |
6. Enable IPv6 IS-IS FRR to calculate a backup next hop through LFA calculation. |
fast-reroute lfa |
By default, IPv6 IS-IS FRR is disabled. |
Configuring IPv6 IS-IS FRR using a routing policy
You can use the apply ipv6 fast-reroute backup-interface command to specify a backup next hop in a routing policy for routes matching specific criteria. You can also perform this task to reference the routing policy for IPv6 IS-IS FRR. For more information about the apply ipv6 fast-reroute backup-interface command and routing policy configurations, see "Configuring routing policies."
To configure IPv6 IS-IS FRR using a routing policy:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. (Optional.) Disable LFA calculation on the interface. |
isis ipv6 fast-reroute lfa-backup exclude |
By default, the interface participates in LFA calculation, and can be elected as a backup interface. |
4. Return to system view. |
quit |
N/A |
5. Enter IS-IS IPv6 unicast address family view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
address-family ipv6 [ unicast ] |
||
6. Enable IPv6 IS-IS FRR using a routing policy. |
fast-reroute route-policy route-policy-name |
By default, IPv6 IS-IS FRR is disabled. |
Enabling BFD for IPv6 IS-IS FRR
By default, IPv6 IS-IS FRR does not use BFD to detect primary link failures. To speed up IPv6 IS-IS convergence, enable BFD for IPv6 IS-IS FRR to detect primary link failures.
To enable BFD control packet mode for IPv6 IS-IS FRR:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Enable BFD control packet mode for IPv6 IS-IS FRR. |
isis ipv6 primary-path-detect bfd ctrl |
By default, BFD control packet mode for IPv6 IS-IS FRR is disabled. |
To enable BFD echo packet mode for IPv6 IS-IS FRR:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Configure the source IPv6 address of BFD echo packets. |
bfd echo-source-ipv6 ip-address |
By default, the source IPv6 address of BFD echo packets is not configured. The source IPv6 address cannot be on the same network segment as any local interface's IP address. For more information, see High Availability Command Reference. |
3. Enter interface view. |
interface interface-type interface-number |
N/A |
4. Enable BFD echo packet mode for IPv6 IS-IS FRR. |
isis ipv6 primary-path-detect bfd echo |
By default, BFD echo packet mode for IPv6 IS-IS FRR is disabled. |
Enabling IPv6 IS-IS MTR
On a network, IPv4 and IPv6 topologies must be consistent so that both IPv6 IS-IS and IPv4 IS-IS can use the SPF algorithm to perform route calculation. If they are different, routers supporting both IPv4 and IPv6 might send IPv6 packets to routers that do not support IPv6, resulting in packet loss.
To resolve this issue, configure IPv6 IS-IS Multi-Topology Routing (MTR) to perform route calculation separately in IPv4 and IPv6 topologies.
As shown in Figure 106, the numbers refer to the link costs. Router A, Router B, and Router D support both IPv4 and IPv6. Router C supports only IPv4 and cannot forward IPv6 packets.
Enable IPv6 IS-IS MTR on Router A, Router B, Router C, and Router D to make them perform route calculation separately in IPv4 and IPv6 topologies. With this configuration, Router A does not forward IPv6 packets destined to Router D through Router B, avoiding packet loss.
Configuration prerequisites
Before you configure IPv6 IS-IS MTR, configure basic IPv4 and IPv6 IS-IS functions, and establish IS-IS neighbors.
Configuration procedure
To enable IPv6 IS-IS MTR:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IS-IS view. |
isis [ process-id ] [ vpn-instance vpn-instance-name ] |
N/A |
3. Specify an IS-IS cost style. |
cost-style { wide | wide-compatible | compatible } |
By default, the IS-IS cost style is narrow. |
4. Enter IPv6 address family view. |
address-family ipv6 [ unicast ] |
N/A |
5. Enable IPv6 IS-IS MTR. |
multi-topology [ compatible ] |
By default, IPv6 IS-IS MTR is disabled. |
Displaying and maintaining IPv6 IS-IS
Execute display commands in any view. For other display and reset commands, see "Configuring IS-IS."
Command |
|
Display information about routes redistributed by IPv6 IS-IS. |
display isis redistribute ipv6 [ ipv6-address mask-length ] [ level-1 | level-2 ] [ process-id ] |
Display IPv6 IS-IS routing information. |
display isis route ipv6 [ ipv6-address ] [ [ level-1 | level-2 ] | verbose ] * [ process-id ] |
Display IPv6 IS-IS topology information. |
display isis spf-tree ipv6 [ [ level-1 | level-2 ] | verbose ] * [ process-id ] |
Display IPv6 IS-IS statistics. |
display isis statistics ipv6 [ level-1 | level-1-2 | level-2 ] [ process-id ] |
Display IPv6 IS-IS route calculation log information. |
display isis event-log spf ipv6 [ [ level-1 | level-2 ] | verbose ] * [ process-id ] |
IPv6 IS-IS configuration examples
IPv6 IS-IS basic configuration example
Network requirements
As shown in Figure 107, Switch A, Switch B, Switch C, and Switch D, all enabled with IPv6, reside in the same AS. Configure IPv6 IS-IS on the switches so that they can reach each other.
Switch A and Switch B are Level-1 switches, Switch D is a Level-2 switch, and Switch C is a Level-1-2 switch.
Configuration procedure
1. Configure IPv6 addresses for interfaces. (Details not shown.)
2. Configure IPv6 IS-IS:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] isis 1
[SwitchA-isis-1] is-level level-1
[SwitchA-isis-1] network-entity 10.0000.0000.0001.00
[SwitchA-isis-1] address-family ipv6
[SwitchA-isis-1-ipv6] quit
[SwitchA-isis-1] quit
[SwitchA] interface vlan-interface 100
[SwitchA-Vlan-interface100] isis ipv6 enable 1
[SwitchA-Vlan-interface100] quit
# Configure Switch B.
<SwitchB> system-view
[SwitchB] isis 1
[SwitchB-isis-1] is-level level-1
[SwitchB-isis-1] network-entity 10.0000.0000.0002.00
[SwitchB-isis-1] address-family ipv6
[SwitchB-isis-1-ipv6] quit
[SwitchB-isis-1] quit
[SwitchB] interface vlan-interface 200
[SwitchB-Vlan-interface200] isis ipv6 enable 1
[SwitchB-Vlan-interface200] quit
# Configure Switch C.
<SwitchC> system-view
[SwitchC] isis 1
[SwitchC-isis-1] network-entity 10.0000.0000.0003.00
[SwitchC-isis-1] address-family ipv6
[SwitchC-isis-1-ipv6] quit
[SwitchC-isis-1] quit
[SwitchC] interface vlan-interface 100
[SwitchC-Vlan-interface100] isis ipv6 enable 1
[SwitchC-Vlan-interface100] quit
[SwitchC] interface vlan-interface 200
[SwitchC-Vlan-interface200] isis ipv6 enable 1
[SwitchC-Vlan-interface200] quit
[SwitchC] interface vlan-interface 300
[SwitchC-Vlan-interface300] isis ipv6 enable 1
[SwitchC-Vlan-interface300] quit
# Configure Switch D.
<SwitchD> system-view
[SwitchD] isis 1
[SwitchD-isis-1] is-level level-2
[SwitchD-isis-1] network-entity 20.0000.0000.0004.00
[SwitchD-isis-1] address-family ipv6
[SwitchD-isis-1-ipv6] quit
[SwitchD-isis-1] quit
[SwitchD] interface vlan-interface 300
[SwitchD-Vlan-interface300] isis ipv6 enable 1
[SwitchD-Vlan-interface300] quit
[SwitchD] interface vlan-interface 301
[SwitchD-Vlan-interface301] isis ipv6 enable 1
[SwitchD-Vlan-interface301] quit
Verifying the configuration
# Display the IPv6 IS-IS routing table on Switch A.
[SwitchA] display isis route ipv6
Route information for IS-IS(1)
------------------------------
Level-1 IPv6 Forwarding Table
-----------------------------
Destination : :: PrefixLen: 0
Flag : R/-/- Cost : 10
Next Hop : FE80::200:FF:FE0F:4 Interface: Vlan100
Destination : 2001:1:: PrefixLen: 64
Flag : D/L/- Cost : 10
Next Hop : Direct Interface: Vlan100
Destination : 2001:2:: PrefixLen: 64
Flag : R/-/- Cost : 20
Next Hop : FE80::200:FF:FE0F:4 Interface: Vlan100
Destination : 2001:3:: PrefixLen: 64
Flag : R/-/- Cost : 20
Next Hop : FE80::200:FF:FE0F:4 Interface: Vlan100
Flags: D-Direct, R-Added to Rib, L-Advertised in LSPs, U-Up/Down Bit Set
# Display the IPv6 IS-IS routing table on Switch B.
[SwitchB] display isis route ipv6
Route information for IS-IS(1)
------------------------------
Level-1 IPv6 Forwarding Table
-----------------------------
Destination : :: PrefixLen: 0
Flag : R/-/- Cost : 10
Next Hop : FE80::200:FF:FE0F:4 Interface: Vlan200
Destination : 2001:1:: PrefixLen: 64
Flag : D/L/- Cost : 10
Next Hop : FE80::200:FF:FE0F:4 Interface: Vlan200
Destination : 2001:2:: PrefixLen: 64
Flag : R/-/- Cost : 20
Next Hop : Direct Interface: Vlan200
Destination : 2001:3:: PrefixLen: 64
Flag : R/-/- Cost : 20
Next Hop : FE80::200:FF:FE0F:4 Interface: Vlan200
Flags: D-Direct, R-Added to Rib, L-Advertised in LSPs, U-Up/Down Bit Set
# Display the IPv6 IS-IS routing table on Switch C.
[SwitchC] display isis route ipv6
Route information for IS-IS(1)
------------------------------
Level-1 IPv6 Forwarding Table
-----------------------------
Destination : 2001:1:: PrefixLen: 64
Flag : D/L/- Cost : 10
Next Hop : Direct Interface: Vlan100
Destination : 2001:2:: PrefixLen: 64
Flag : D/L/- Cost : 10
Next Hop : Direct Interface: Vlan200
Destination : 2001:3:: PrefixLen: 64
Flag : D/L/- Cost : 10
Next Hop : Direct Interface: Vlan300
Flags: D-Direct, R-Added to Rib, L-Advertised in LSPs, U-Up/Down Bit Set
Level-2 IPv6 Forwarding Table
-----------------------------
Destination : 2001:1:: PrefixLen: 64
Flag : D/L/- Cost : 10
Next Hop : Direct Interface: Vlan100
Destination : 2001:2:: PrefixLen: 64
Flag : D/L/- Cost : 10
Next Hop : Direct Interface: Vlan200
Destination : 2001:3:: PrefixLen: 64
Flag : D/L/- Cost : 10
Next Hop : Direct Interface: Vlan300
Destination : 2001:4::1 PrefixLen: 128
Flag : R/-/- Cost : 10
Next Hop : FE80::20F:E2FF:FE3E:FA3D Interface: Vlan300
Flags: D-Direct, R-Added to Rib, L-Advertised in LSPs, U-Up/Down Bit Set
# Display the IPv6 IS-IS routing table on Switch D.
[SwitchD] display isis route ipv6
Route information for IS-IS(1)
------------------------------
Level-2 IPv6 Forwarding Table
-----------------------------
Destination : 2001:1:: PrefixLen: 64
Flag : R/-/- Cost : 20
Next Hop : FE80::200:FF:FE0F:4 Interface: Vlan300
Destination : 2001:2:: PrefixLen: 64
Flag : R/-/- Cost : 20
Next Hop : FE80::200:FF:FE0F:4 Interface: Vlan300
Destination : 2001:3:: PrefixLen: 64
Flag : D/L/- Cost : 10
Next Hop : Direct Interface: Vlan300
Destination : 2001:4::1 PrefixLen: 128
Flag : D/L/- Cost : 0
Next Hop : Direct Interface: Loop1
Flags: D-Direct, R-Added to Rib, L-Advertised in LSPs, U-Up/Down Bit Set
BFD for IPv6 IS-IS configuration example
Network requirements
As shown in Figure 108:
· Configure IPv6 IS-IS on Switch A and Switch B so that they can reach other.
· Enable BFD on VLAN-interface 10 of Switch A and Switch B.
After the link between Switch B and the Layer-2 switch fails, BFD can quickly detect the failure and notify IPv6 IS-IS of the failure. Then Switch A and Switch B communicate through Switch C.
Table 27 Interface and IP address assignment
Device |
Interface |
IPv6 address |
Switch A |
Vlan-int10 |
2001::1/64 |
Switch A |
Vlan-int11 |
2001:2::1/64 |
Switch B |
Vlan-int10 |
2001::2/64 |
Switch B |
Vlan-int13 |
2001:3::2/64 |
Switch C |
Vlan-int11 |
2001:2::2/64 |
Switch C |
Vlan-int13 |
2001:3::1/64 |
Configuration procedure
1. Configure IPv6 addresses for interfaces. (Details not shown.)
2. Configure IPv6 IS-IS:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] isis 1
[SwitchA-isis-1] is-level level-1
[SwitchA-isis-1] network-entity 10.0000.0000.0001.00
[SwitchA-isis-1] address-family ipv6
[SwitchA-isis-1-ipv6] quit
[SwitchA-isis-1] quit
[SwitchA] interface vlan-interface 10
[SwitchA-Vlan-interface10] isis ipv6 enable 1
[SwitchA-Vlan-interface10] quit
[SwitchA] interface vlan-interface 11
[SwitchA-Vlan-interface11] isis ipv6 enable 1
[SwitchA-Vlan-interface11] quit
# Configure Switch B.
<SwitchB> system-view
[SwitchB] isis 1
[SwitchB-isis-1] is-level level-1
[SwitchB-isis-1] network-entity 10.0000.0000.0002.00
[SwitchB-isis-1] address-family ipv6
[SwitchB-isis-1-ipv6] quit
[SwitchB-isis-1] quit
[SwitchB] interface vlan-interface 10
[SwitchB-Vlan-interface10] isis ipv6 enable 1
[SwitchB-Vlan-interface10] quit
[SwitchB] interface vlan-interface 13
[SwitchB-Vlan-interface13] isis ipv6 enable 1
[SwitchB-Vlan-interface13] quit
# Configure Switch C.
<SwitchC> system-view
[SwitchC] isis 1
[SwitchC-isis-1] network-entity 10.0000.0000.0003.00
[SwitchC-isis-1] address-family ipv6
[SwitchC-isis-1-ipv6] quit
[SwitchC-isis-1] quit
[SwitchC] interface vlan-interface 11
[SwitchC-Vlan-interface11] isis ipv6 enable 1
[SwitchC-Vlan-interface11] quit
[SwitchC] interface vlan-interface 13
[SwitchC-Vlan-interface13] isis ipv6 enable 1
[SwitchC-Vlan-interface13] quit
3. Configure BFD functions:
# Enable BFD and configure BFD parameters on Switch A.
[SwitchA] bfd session init-mode active
[SwitchA] interface vlan-interface 10
[SwitchA-Vlan-interface10] isis ipv6 bfd enable
[SwitchA-Vlan-interface10] bfd min-transmit-interval 500
[SwitchA-Vlan-interface10] bfd min-receive-interval 500
[SwitchA-Vlan-interface10] bfd detect-multiplier 7
[SwitchA-Vlan-interface10] return
# Enable BFD and configure BFD parameters on Switch B.
[SwitchB] bfd session init-mode active
[SwitchB] interface vlan-interface 10
[SwitchB-Vlan-interface10] isis ipv6 bfd enable
[SwitchB-Vlan-interface10] bfd min-transmit-interval 500
[SwitchB-Vlan-interface10] bfd min-receive-interval 500
[SwitchB-Vlan-interface10] bfd detect-multiplier 6
Verifying the configuration
# Display BFD session information on Switch A.
<SwitchA> display bfd session
Total Session Num: 1 Init Mode: Active
IPv6 Session Working Under Ctrl Mode:
Local Discr: 1441 Remote Discr: 1450
Source IP: FE80::20F:FF:FE00:1202 (link-local address of VLAN-interface 10 on Switch A)
Destination IP: FE80::20F:FF:FE00:1200 (link-local address of VLAN-interface 10 on Switch B)
Session State: Up Interface: Vlan10
Hold Time: 2319ms
# Display routes destined for 2001:4::0/64 on Switch A.
<SwitchA> display ipv6 routing-table 2001:4::0 64
Summary Count : 1
Destination: 2001:4::/64 Protocol : IS_L1
NextHop : FE80::20F:FF:FE00:1200 Preference: 15
Interface : Vlan10 Cost : 10
The output shows that Switch A and Switch B communicate through VLAN-interface 10. Then the link over VLAN-interface 10 fails.
# Display routes destined for 2001:4::0/64 on Switch A.
<SwitchA> display ipv6 routing-table 2001:4::0 64
Summary Count : 1
Destination: 2001:4::/64 Protocol : IS_L1
NextHop : FE80::BAAF:67FF:FE27:DCD0 Preference: 15
Interface : Vlan11 Cost : 20
The output shows that Switch A and Switch B communicate through VLAN-interface 11.
IPv6 IS-IS FRR configuration example
Network requirements
As shown in Figure 109, Switch A, Switch B, and Switch C belong to the same IS-IS routing domain. Configure IPv6 IS-IS FRR so that when the Link A fails, traffic can be switched to Link B immediately.
Table 28 Interface and IP address assignment
Device |
Interface |
IP address |
Device |
Interface |
IP address |
Switch A |
Vlan-int100 |
1::1/64 |
Switch B |
Vlan-int101 |
3::1/64 |
|
Vlan-int200 |
2::1/64 |
|
Vlan-int200 |
2::2/64 |
|
Loop0 |
10::1/128 |
|
Loop0 |
20::1/128 |
Switch C |
Vlan-int100 |
1::2/64 |
|
|
|
|
Vlan-int101 |
3::2/64 |
|
|
|
Configuration procedure
1. Configure IPv6 addresses for interfaces on the switches and enable IPv6 IS-IS. (Details not shown.)
2. Configure IPv6 IS-IS on the switches to make sure Switch A, Switch B, and Switch C can communicate with each other at Layer 3. (Details not shown.)
3. Configure IPv6 IS-IS FRR:
Enable IPv6 IS-IS FRR to calculate a backup next hop through LFA calculation, or designate a backup next hop by using a referenced routing policy.
? (Method 1.) Enable IPv6 IS-IS FRR to calculate a backup next hop through LFA calculation:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] isis 1
[SwitchA-isis-1] address-family ipv6
[SwitchA-isis-1-ipv6] fast-reroute lfa
# Configure Switch B.
<SwitchB> system-view
[SwitchB] isis 1
[SwitchB-isis-1] address-family ipv6
[SwitchB-isis-1-ipv6] fast-reroute lfa
? (Method 2.) Enable IPv6 IS-IS FRR to designate a backup next hop by using a routing policy:
# Configure Switch A.
<SwitchA> system-view
[SwitchA] ipv6 prefix-list abc index 10 permit 20:: 128
[SwitchA] route-policy frr permit node 10
[SwitchA-route-policy-frr-10] if-match ipv6 address prefix-list abc
[SwitchA-route-policy-frr-10] apply ipv6 fast-reroute backup-interface vlan-interface 100 backup-nexthop 1::2
[SwitchA-route-policy-frr-10] quit
[SwitchA] isis 1
[SwitchA-isis-1] address-family ipv6
[SwitchA-isis-1-ipv6] fast-reroute route-policy frr
[SwitchA-isis-1-ipv6] quit
[SwitchA-isis-1] quit
# Configure Switch B.
<SwitchB> system-view
[SwitchB] ipv6 prefix-list abc index 10 permit 10:: 128
[SwitchB] route-policy frr permit node 10
[SwitchB-route-policy-frr-10] if-match ipv6 address prefix-list abc
[SwitchB-route-policy-frr-10] apply ipv6 fast-reroute backup-interface vlan-interface 101 backup-nexthop 3::2
[SwitchB-route-policy-frr-10] quit
[SwitchB] isis 1
[SwitchB-isis-1] address-family ipv6
[SwitchB-isis-1-ipv6] fast-reroute route-policy frr
[SwitchB-isis-1-ipv6] quit
[SwitchB-isis-1] quit
Verifying the configuration
# Display route 20::1/128 on Switch A to view the backup next hop information.
[SwitchA] display ipv6 routing-table 20::1 128 verbose
Summary count : 1
Destination: 20::1/128
Protocol: IS_L1
Process ID: 1
SubProtID: 0x1 Age: 00h27m45s
Cost: 10 Preference: 15
IpPre: N/A QosLocalID: N/A
Tag: 0 State: Active Adv
OrigTblID: 0xa OrigVrf: default-vrf
TableID: 0xa OrigAs: 0
NibID: 0x24000005 LastAs: 0
AttrID: 0xffffffff Neighbor: ::
Flags: 0x10041 OrigNextHop: FE80::34CD:9FF:FE2F:D02
Label: NULL RealNextHop: FE80::34CD:9FF:FE2F:D02
BkLabel: NULL BkNextHop: FE80::7685:45FF:FEAD:102
Tunnel ID: Invalid Interface: Vlan-interface200
BkTunnel ID: Invalid BkInterface: Vlan-interface100
FtnIndex: 0x0 TrafficIndex: N/A
Connector: N/A
# Display route 10::1/128 on Switch B to view the backup next hop information.
[SwitchB] display ipv6 routing-table 10::1 128 verbose
Summary count : 1
Destination: 10::1/128
Protocol: IS_L1
Process ID: 1
SubProtID: 0x1 Age: 00h33m23s
Cost: 10 Preference: 15
IpPre: N/A QosLocalID: N/A
Tag: 0 State: Active Adv
OrigTblID: 0xa OrigVrf: default-vrf
TableID: 0xa OrigAs: 0
NibID: 0x24000006 LastAs: 0
AttrID: 0xffffffff Neighbor: ::
Flags: 0x10041 OrigNextHop: FE80::34CC:E8FF:FE5B:C02
Label: NULL RealNextHop: FE80::34CC:E8FF:FE5B:C02
BkLabel: NULL BkNextHop: FE80::7685:45FF:FEAD:102
Tunnel ID: Invalid Interface: Vlan-interface200
BkTunnel ID: Invalid BkInterface: Vlan-interface101
FtnIndex: 0x0 TrafficIndex: N/A
Connector: N/A
Configuring IPv6 PBR
Overview
Policy-based routing (PBR) uses user-defined policies to route packets. A policy can specify the next hop, default next hop, and precedence for packets that match specific criteria such as ACLs.
A device forwards received packets using the following process:
1. The device uses PBR to forward matching packets.
2. If the packets do not match the PBR policy or the PBR-based forwarding fails, the device uses the routing table, excluding the default route, to forward the packets.
3. If the routing table-based forwarding fails, the device uses the default next hop defined in PBR to forward packets.
4. If the default next hop or default output interface-based forwarding fails, the device uses the default route to forward packets.
PBR includes local PBR and interface PBR.
· Local PBR guides the forwarding of locally generated packets, such as the ICMP packets generated by using the ping command.
· Interface PBR guides the forwarding of packets received on an interface only.
Policy
An IPv6 policy includes match criteria and actions to be taken on the matching packets. A policy can have one or multiple nodes as follows:
· Each node is identified by a node number. A smaller node number has a higher priority.
· A node contains if-match and apply clauses. An if-match clause specifies a match criterion, and an apply clause specifies an action.
· A node has a match mode of permit or deny.
An IPv6 policy compares packets with nodes in priority order. If a packet matches the criteria on a node, it is processed by the action on the node. Otherwise, it goes to the next node for a match. If the packet does not match the criteria on any node, it is forwarded according to the routing table.
if-match clause
IPv6 PBR supports only the if-match acl clause to set an ACL match criterion.
apply clause
IPv6 PBR supports the types of apply clauses shown in Table 29. You can specify multiple apply clauses for a node, but some of them might not be executed.
Table 29 Priorities and meanings of apply clauses
Clause |
Meaning |
Priority |
apply precedence |
Sets an IP precedence. |
This clause is always executed. |
apply next-hop |
Sets next hops. |
This clause is always executed. |
apply default-next-hop |
Sets default next hops. |
This clause takes effect only when no next hop is set or the next hop is invalid, and the IPv6 packet does not match any route in the routing table. |
Relationship between the match mode and clauses on the node
Match mode |
||
In permit mode |
In deny mode |
|
Yes |
· If the node is configured with apply clauses, IPv6 PBR executes the apply clauses on the node. If the IPv6 PBR-based forwarding succeeds, IPv6 PBR does not compare the packet with the next node. · If the node is configured with no apply clauses, the packet is forwarded according to the routing table. |
The packet is forwarded according to the routing table. |
No |
IPv6 PBR compares the packet with the next node. |
IPv6 PBR compares the packet with the next node. |
A node that has no if-match clauses matches any packet.
IPv6 PBR and Track
IPv6 PBR can work with the Track feature to dynamically adapt the availability status of an apply clause to the link status of a tracked object. The tracked object can be a next hop or default next hop.
· When the track entry associated with an object changes to Negative, the apply clause is invalid.
· When the track entry changes to Positive or NotReady, the apply clause is valid.
For more information about Track-IPv6 PBR collaboration, see High Availability Configuration Guide.
Restrictions and guidelines: IPv6 PBR configuration
If a packet destined for the local device matches an IPv6 PBR policy, IPv6 PBR will execute the apply clauses in the policy, including the clause for forwarding. When you configure an IPv6 PBR policy, be careful to avoid this situation.
IPv6 PBR configuration task list
Tasks at a glance |
(Required.) Configuring an IPv6 policy: |
(Required.) Configuring IPv6 PBR: |
Configuring an IPv6 policy
Creating an IPv6 node
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Create an IPv6 policy or policy node and enter its view. |
ipv6 policy-based-route policy-name [ deny | permit ] node node-number |
By default, no IPv6 policy nodes exist. |
Setting match criteria for an IPv6 node
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IPv6 policy node view. |
ipv6 policy-based-route policy-name [ deny | permit ] node node-number |
N/A |
3. Set an ACL match criterion. |
if-match acl { ipv6-acl-number | name ipv6-acl-name } |
By default, no ACL match criterion is set. The ACL match criterion cannot match Layer 2 information. |
|
NOTE: If an ACL match criterion is defined, packets are compared with the ACL rule. The permit or deny action and the time range of the specified ACL are ignored. If the specified ACL does not exist, no packet is matched. |
Configuring actions for an IPv6 node
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter IPv6 policy node view. |
ipv6 policy-based-route policy-name [ deny | permit ] node node-number |
N/A |
3. Set an IP precedence. |
apply precedence { type | value } |
By default, no IP precedence is specified. |
4. Set next hops for permitted IPv6 packets. |
apply next-hop [ vpn-instance vpn-instance-name ] { ipv6-address [ direct ] [ track track-entry-number ] }&<1-n> |
By default, no next hop is specified. You can specify multiple next hops for backup in one command line or by executing this command multiple times. You can specify a maximum of two next hops for a node. |
5. Set default next hops. |
apply default-next-hop [ vpn-instance vpn-instance-name ] { ipv6-address [ direct ] [ track track-entry-number ] }&<1-n> |
By default, no default next hop is specified. You can specify multiple default next hops for backup in one command line or by executing this command multiple times. You can specify a maximum of two default next hops for a node. |
Configuring IPv6 PBR
Configuring IPv6 local PBR
Configure IPv6 PBR by applying a policy locally. IPv6 PBR uses the policy to guide the forwarding of locally generated packets. The specified policy must already exist. Otherwise, the IPv6 local PBR configuration fails.
You can apply only one policy locally. Before you apply a new policy, you must first remove the current policy.
IPv6 local PBR might affect local services, such as ping and Telnet. Do not configure IPv6 local PBR unless doing so is required.
To configure IPv6 local PBR:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Apply a policy locally. |
ipv6 local policy-based-route policy-name |
By default, no policy is locally applied. |
Configuring IPv6 interface PBR
Configure IPv6 PBR by applying an IPv6 policy to an interface. IPv6 PBR uses the policy to guide the forwarding of IPv6 packets received on the interface. The specified policy must already exist. Otherwise, the IPv6 interface PBR configuration fails.
You can apply only one policy to an interface. Before you apply a new policy, you must first remove the current policy from the interface.
You can apply a policy to multiple interfaces.
To configure IPv6 interface PBR:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter interface view. |
interface interface-type interface-number |
N/A |
3. Apply an IPv6 policy to the interface. |
ipv6 policy-based-route policy-name |
By default, no IPv6 policy is applied to the interface. |
4. Quit interface view. |
quit |
N/A |
5. (Optional.) Specify an IPv6 policy for a list of VLAN interfaces. |
ipv6 policy-based-route policy-name apply vlan-interface interface-list |
By default, no IPv6 policy is applied to the specified VLAN interfaces. When you want to specify an IPv6 policy for multiple VLAN interfaces on a device, use this command to simplify configuration and save device resources. |
Displaying and maintaining IPv6 PBR
Execute display commands in any view and reset commands in user view.
Task |
Command |
Display IPv6 PBR policy information. |
display ipv6 policy-based-route [ policy policy-name ] |
(In standalone mode.) Display the IPv6 PBR configuration and statistics for a VLAN interface. |
display ipv6 policy-based-route apply vlan-interface interface-number [ slot slot-number ] |
(In IRF mode.) Display the IPv6 PBR configuration and statistics for a VLAN interface. |
display ipv6 policy-based-route apply vlan-interface interface-number [ chassis chassis-number slot slot-number ] |
Display IPv6 PBR configuration. |
display ipv6 policy-based-route setup |
(In standalone mode.) Display IPv6 local PBR configuration and statistics. |
display ipv6 policy-based-route local [ slot slot-number ] |
(In IRF mode.) Display IPv6 local PBR configuration and statistics. |
display ipv6 policy-based-route local [ chassis chassis-number slot slot-number ] |
(In standalone mode.) Display IPv6 interface PBR configuration and statistics. |
display ipv6 policy-based-route interface interface-type interface-number [ slot slot-number ] |
(In IRF mode.) Display IPv6 interface PBR configuration and statistics. |
display ipv6 policy-based-route interface interface-type interface-number [ chassis chassis-number slot slot-number ] |
Clear IPv6 PBR statistics. |
reset ipv6 policy-based-route statistics [ policy policy-name ] |
IPv6 PBR configuration examples
Packet type-based IPv6 local PBR configuration example
Network requirements
As shown in Figure 110, Switch B and Switch C cannot reach each other. Configure IPv6 PBR on Switch A to forward all TCP packets to the next hop 1::2. Switch A forwards other packets according to the routing table.
Configuration procedure
1. Configure Switch A:
# Create VLAN 10 and VLAN 20.
<SwitchA> system-view
[SwitchA] vlan 10
[SwitchA-vlan10] quit
[SwitchA] vlan 20
[SwitchA-vlan20] quit
# Configure the IPv6 addresses of VLAN-interface 10 and VLAN-interface 20.
[SwitchA] interface vlan-interface 10
[SwitchA-Vlan-interface10] ipv6 address 1::1 64
[SwitchA-Vlan-interface10] quit
[SwitchA] interface vlan-interface 20
[SwitchA-Vlan-interface20] ipv6 address 2::1 64
[SwitchA-Vlan-interface20] quit
# Configure ACL 3001 to match TCP packets.
[SwitchA] acl ipv6 advanced 3001
[SwitchA-acl-ipv6-adv-3001] rule permit tcp
[SwitchA-acl-ipv6-adv-3001] quit
# Configure Node 5 for policy aaa to forward TCP packets to next hop 1::2.
[SwitchA] ipv6 policy-based-route aaa permit node 5
[SwitchA-pbr6-aaa-5] if-match acl 3001
[SwitchA-pbr6-aaa-5] apply next-hop 1::2
[SwitchA-pbr6-aaa-5] quit
# Configure IPv6 local PBR by applying policy aaa to Switch A.
[SwitchA] ipv6 local policy-based-route aaa
2. Configure Switch B:
# Create VLAN 10.
<SwitchB> system-view
[SwitchB] vlan 10
[SwitchB-vlan10] quit
# Configure the IPv6 address of VLAN-interface 10.
[SwitchB] interface vlan-interface 10
[SwitchB-Vlan-interface10] ipv6 address 1::2 64
3. Configure Switch C:
# Create VLAN 20.
<SwitchC> system-view
[SwitchC] vlan 20
[SwitchC-vlan20] quit
# Configure the IPv6 address of VLAN-interface 20.
[SwitchC] interface vlan-interface 20
[SwitchC-Vlan-interface20] ipv6 address 2::2 64
Verifying the configuration
# Telnet to Switch B on Switch A. The operation succeeds.
# Telnet to Switch C on Switch A. The operation fails.
# Ping Switch C from Switch A. The operation succeeds.
Telnet uses TCP and ping uses ICMP. The results show the following:
· All TCP packets sent from Switch A are forwarded to the next hop 1::2.
· Other packets are forwarded through VLAN-interface 20.
· The IPv6 local PBR configuration is effective.
Packet type-based IPv6 interface PBR configuration example
Network requirements
As shown in Figure 111, Switch B and Switch C cannot reach each other. Configure IPv6 PBR on Switch A to forward all TCP packets received on VLAN-interface 11 to the next hop 1::2. Switch A forwards other IPv6 packets according to the routing table.
Configuration procedure
1. Configure Switch A:
# Create VLAN 10 and VLAN 20.
<SwitchA> system-view
[SwitchA] vlan 10
[SwitchA-vlan10] quit
[SwitchA] vlan 20
[SwitchA-vlan20] quit
# Configure RIPng.
[SwitchA] ripng 1
[SwitchA-ripng-1] quit
[SwitchA] interface vlan-interface 10
[SwitchA-Vlan-interface10] ipv6 address 1::1 64
[SwitchA-Vlan-interface10] ripng 1 enable
[SwitchA-Vlan-interface10] quit
[SwitchA] interface vlan-interface 20
[SwitchA-Vlan-interface20] ipv6 address 2::1 64
[SwitchA-Vlan-interface20] ripng 1 enable
[SwitchA-Vlan-interface20] quit
# Configure ACL 3001 to match TCP packets.
[SwitchA] acl ipv6 advanced 3001
[SwitchA-acl-ipv6-adv-3001] rule permit tcp
[SwitchA-acl-ipv6-adv-3001] quit
# Configure Node 5 for policy aaa to forward TCP packets to next hop 1::2.
[SwitchA] ipv6 policy-based-route aaa permit node 5
[SwitchA-pbr6-aaa-5] if-match acl 3001
[SwitchA-pbr6-aaa-5] apply next-hop 1::2
[SwitchA-pbr6-aaa-5] quit
# Configure IPv6 interface PBR by applying policy aaa to VLAN-interface 11.
[SwitchA] interface vlan-interface 11
[SwitchA-Vlan-interface11] ipv6 address 10::2 64
[SwitchA-Vlan-interface11] undo ipv6 nd ra halt
[SwitchA-Vlan-interface11] ripng 1 enable
[SwitchA-Vlan-interface11] ipv6 policy-based-route aaa
2. Configure Switch B:
# Create VLAN 10.
<SwitchB> system-view
[SwitchB] vlan 10
[SwitchB-vlan10] quit
# Configure RIPng.
[SwitchB] ripng 1
[SwitchB-ripng-1] quit
[SwitchB] interface vlan-interface 10
[SwitchB-Vlan-interface10] ipv6 address 1::2 64
[SwitchB-Vlan-interface10] ripng 1 enable
[SwitchB-Vlan-interface10] quit
3. Configure Switch C:
# Create VLAN 20.
<SwitchC> system-view
[SwitchC] vlan 20
[SwitchC-vlan20] quit
# Configure RIPng.
[SwitchC] ripng 1
[SwitchC-ripng-1] quit
[SwitchC] interface vlan-interface 20
[SwitchC-Vlan-interface20] ipv6 address 2::2 64
[SwitchC-Vlan-interface20] ripng 1 enable
[SwitchC-Vlan-interface20] quit
Verifying the configuration
# Enable IPv6 and configure the IPv6 address 10::3 for Host A.
C:\>ipv6 install
Installing...
Succeeded.
C:\>ipv6 adu 4/10::3
# On Host A, Telnet to Switch B that is directly connected to Switch A. The operation succeeds.
# On Host A, Telnet to Switch C that is directly connected to Switch A. The operation fails.
# Ping Switch C from Host A. The operation succeeds.
Telnet uses TCP, and ping uses ICMP. The results show the following:
· All TCP packets arriving on VLAN-interface 11 of Switch A are forwarded to next hop 1::2.
· Other packets are forwarded through VLAN-interface 20.
· The IPv6 interface PBR configuration is effective.
Configuring routing policies
Overview
Routing policies control routing paths by filtering and modifying routing information. This chapter describes both IPv4 and IPv6 routing policies.
Routing policies can filter advertised, received, and redistributed routes, and modify attributes for specific routes.
To configure a routing policy:
1. Configure filters based on route attributes, such as destination address and the advertising router's address.
2. Create a routing policy and apply filters to the routing policy.
Filters
Routing policies can use the following filters to match routes.
ACL
ACLs include IPv4 ACLs and IPv6 ACLs. An ACL can match the destination or next hop of routes.
For more information about ACLs, see ACL and QoS Configuration Guide.
IP prefix list
IP prefix lists include IPv4 prefix lists and IPv6 prefix lists.
An IP prefix list matches the destination address of routes. You can use the gateway option to receive routes only from specific routers. For more information about the gateway option, see "Configuring RIP" and "Configuring OSPF."
An IP prefix list can contain multiple items that specify prefix ranges. Each destination IP address prefix of a route is compared with these items in ascending order of their index numbers. A prefix matches the IP prefix list if it matches one item in the list.
AS path list
An AS path list matches the AS_PATH attribute of BGP routes.
For more information about AS path lists, see "Configuring BGP."
Community list
A community list matches the COMMUNITY attribute of BGP routes.
For more information about community lists, see "Configuring BGP."
Extended community list
An extended community list matches the extended community attribute (Route-Target for VPN and Site of Origin) of BGP routes.
For more information about extended community lists, see MPLS Configuration Guide.
Routing policy
A routing policy can contain multiple nodes, which are in a logical OR relationship. A node with a smaller number is matched first. A route matches the routing policy if it matches one node (except the node configured with the continue clause) in the routing policy.
Each node has a match mode of permit or deny.
· permit—Specifies the permit match mode for a routing policy node. If a route meets all the if-match clauses of the node, it is handled by the apply clauses of the node. The route is not compared with the next node unless the continue clause is configured. If a route does not meet all the if-match clauses of the node, it is compared with the next node.
· deny—Specifies the deny match mode for a routing policy node. The apply and continue clauses of a deny node are never executed. If a route meets all the if-match clauses of the node, it is denied without being compared with the next node. If a route does not meet all the if-match clauses of the node, it is compared with the next node.
A node can contain a set of if-match, apply, and continue clauses.
· if-match clauses—Specify the match criteria that match the attributes of routes. The if-match clauses are in a logical AND relationship. A route must meet all the if-match clauses to match the node.
· apply clauses—Specify the actions to be taken on permitted routes, such as modifying a route attribute.
· continue clause—Specifies the next node. A route that matches the current node (permit node) must match the specified next node in the same routing policy. The continue clause combines the if-match and apply clauses of the two nodes to improve flexibility of the routing policy.
Follow these guidelines when you configure if-match, apply, and continue clauses:
· If you only want to filter routes, do not configure apply clauses.
· If you do not configure any if-match clauses for a permit node, the node will permit all routes.
· Configure a permit node containing no if-match or apply clauses following multiple deny nodes to allow unmatched routes to pass.
Configuring filters
Configuration prerequisites
Determine the IP prefix list name, matching address range, and community list number.
Configuring an IP prefix list
Configuring an IPv4 prefix list
If all the items are set to deny mode, no routes can pass the IPv4 prefix list. To permit unmatched IPv4 routes, you must configure the permit 0.0.0.0 0 less-equal 32 item following multiple deny items.
To configure an IPv4 prefix list:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Configure an IPv4 prefix list. |
ip prefix-list prefix-list-name [ index index-number ] { deny | permit } ip-address mask-length [ greater-equal min-mask-length ] [ less-equal max-mask-length ] |
By default, no IPv4 prefix lists exist. |
Configuring an IPv6 prefix list
If all items are set to deny mode, no routes can pass the IPv6 prefix list. To permit unmatched IPv6 routes, you must configure the permit :: 0 less-equal 128 item following multiple deny items.
To configure an IPv6 prefix list:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Configure an IPv6 prefix list. |
ipv6 prefix-list prefix-list-name [ index index-number ] { deny | permit } ipv6-address { prefix-length | inverse inverse-prefix-length [ greater-equal min-prefix-length ] [ less-equal max-prefix-length ] } |
By default, no IPv6 prefix lists exist. |
Configuring an AS path list
You can configure multiple items for an AS path list that is identified by a number. The relationship between the items is logical OR. A route matches the AS path list if it matches one item in the list.
To configure an AS path list:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Configure an AS path list. |
ip as-path as-path-number { deny | permit } regular-expression |
By default, no AS path lists exist. |
Configuring a community list
You can configure multiple items for a community list that is identified by a number. The relationship between the items is logical OR. A route matches the community list if it matches one item in the list.
To configure a community list:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Configure a community list. |
·
Configure a basic community list: ·
Configure an advanced community list: |
By default, no community lists exist. |
Configuring an extended community list
You can configure multiple items for an extended community list that is identified by a number. The relationship between the items is logical OR. A route matches the extended community list if it matches one item in the list.
To configure an extended community list:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Configure an extended community list. |
ip extcommunity-list ext-comm-list-number { deny | permit } { rt route-target | soo site-of-origin }&<1-32> |
By default, no extended community lists exist. |
Configuring a routing policy
Configuration prerequisites
Configure filters and routing protocols, and determine the routing policy name, node numbers, match criteria, and the attributes to be modified.
Creating a routing policy
For a routing policy that has more than one node, configure a minimum of one permit node. A route that does not match any node cannot pass the routing policy. If all the nodes are in deny mode, no routes can pass the routing policy.
To create a routing policy:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Create a routing policy and a node, and enter routing policy node view. |
route-policy route-policy-name { deny | permit } node node-number |
By default, no routing policies exist. |
Configuring if-match clauses
You can either specify no if-match clauses or multiple if-match clauses for a routing policy node. If no if-match clause is specified for a permit node, all routes can pass the node. If no if-match clause is specified for a deny node, no routes can pass the node.
The if-match clauses of a routing policy node have a logical AND relationship. A route must meet all if-match clauses before it can be executed by the apply clauses of the node. If an if-match command exceeds the maximum length, multiple if-match clauses of the same type are generated. These clauses have a logical OR relationship. A route only needs to meet one of them.
To configure if-match clauses:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter routing policy node view. |
route-policy route-policy-name { deny | permit } node node-number |
N/A |
3. Match routes whose destination, next hop, or source address matches an ACL or prefix list. |
·
Match IPv4 routes whose destination, next hop,
or source address matches an ACL or IPv4 prefix list: ·
Match IPv6 routes whose destination, next hop,
or source address matches an ACL or IPv6 prefix list: |
By default, no ACL or prefix list match criterion is configured. If the ACL used by an if-match clause does not exist, the clause is always matched. If no rules of the specified ACL are matched or the match rules are inactive, the clause is not matched. The ACL specified in an if-match clause must be a non-VPN ACL. All IPv6 routes match a node if the if-match clauses of the node use only IPv4 ACLs. All IPv4 routes match a node if the if-match clauses of the node use only IPv6 ACLs. |
4. Match BGP routes whose AS_PATH attribute matches a specified AS path list. |
if-match as-path as-path-number&<1-32> |
By default, no AS path match criterion is configured. |
5. Match BGP routes whose COMMUNITY attribute matches a specified community list. |
if-match community { { basic-community-list-number | name comm-list-name } [ whole-match ] | adv-community-list-number }&<1-32> |
By default, no COMMUNITY match criterion is matched. |
6. Match routes having the specified cost. |
if-match cost cost-value |
By default, no cost match criterion is configured. |
7. Match BGP routes whose extended community attribute matches a specified extended community list. |
if-match extcommunity ext-comm-list-number&<1-32> |
By default, no extended community list match criterion is configured. |
8. Match routes having the specified output interface. |
if-match interface { interface-type interface-number }&<1-16> |
By default, no output interface match criterion is configured. This command is not supported by BGP. |
9. Match BGP routes having the specified local preference. |
if-match local-preference preference |
By default, no local preference is configured for BGP routes. |
10. Match routes having MPLS labels. |
if-match mpls-label |
By default, no MPLS label match criterion is configured. |
11. Match routes having the specified route type. |
if-match route-type { external-type1 | external-type1or2 | external-type2 | internal | is-is-level-1 | is-is-level-2 | nssa-external-type1 | nssa-external-type1or2 | nssa-external-type2 } * |
By default, no route type match criterion is configured. |
12. Match IGP routes having the specified tag value. |
if-match tag tag-value |
By default, no tag match criterion is configured. |
Configuring apply clauses
Except for the apply commands used for setting the next hop for IPv4 and IPv6 routes, all apply commands are the same for IPv4 and IPv6 routing.
To configure apply clauses:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter routing policy node view. |
route-policy route-policy-name { deny | permit } node node-number |
N/A |
3. Set the AS_PATH attribute for BGP routes. |
By default, no AS_PATH attribute is set for BGP routes. |
|
4. Delete the specified COMMUNITY attribute for BGP routes. |
apply comm-list { comm-list-number | comm-list-name } delete |
By default, no COMMUNITY attribute is deleted for BGP routes. |
5. Set the specified COMMUNITY attribute for BGP routes. |
apply community { none | additive | { community-number&<1-32> | aa:nn&<1-32> | internet | no-advertise | no-export | no-export-subconfed } * [ additive ] } |
By default, no community attribute is set for BGP routes. |
6. Set a cost for routes. |
apply cost [ + | - ] cost-value |
By default, no cost is set for routes. |
7. Set a cost type for routes. |
apply cost-type { external | internal | type-1 | type-2 } |
By default, no cost type is set for routes. |
8. Set the extended community attribute for BGP routes. |
apply extcommunity { rt route-target }&<1-32> [ additive ] |
By default, no extended community attribute is set for BGP routes. |
9. Set the next hop for routes. |
·
Set the next hop for IPv4 routes: ·
Set the next hop for IPv6 routes: |
By default, no next hop is set for IPv4 or IPv6 routes. The apply ip-address next-hop and apply ipv6 next-hop commands do not apply to redistributed IPv4 and IPv6 routes. |
10. Set an IP precedence for matching routes. |
apply ip-precedence { value | clear } |
By default, no IP precedence is set. |
11. Redistribute routes to the specified IS-IS level. |
apply isis { level-1 | level-1-2 | level-2 } |
By default, routes are not redistributed into the specified IS-IS level. |
12. Set a local preference for BGP routes. |
apply local-preference preference |
By default, no local preference is set for BGP routes. |
13. Set MPLS labels. |
apply mpls-label |
By default, no MPLS label is set. |
14. Set the ORIGIN attribute for BGP routes. |
apply origin { egp as-number | igp | incomplete } |
By default, no ORIGIN attribute is set for BGP routes. |
15. Set a preference. |
apply preference preference |
By default, no preference is set. |
16. Set a preferred value for BGP routes. |
apply preferred-value preferred-value |
By default, no preferred value is set for BGP routes. |
17. Set a prefix priority. |
apply prefix-priority { critical | high | medium } |
By default, no prefix priority is set, which means the prefix priority is low. |
18. Set a local QoS ID for matching routes. |
apply qos-local-id { local-id-value | clear } |
By default, no local QoS ID is set. |
19. Set a tag value for IGP routes. |
apply tag tag-value |
By default, no tag value is set for IGP routes. |
20. Set a traffic index for BGP routes. |
apply traffic-index { value | clear } |
By default, no traffic index is set for BGP routes. |
21. Set a backup link for fast reroute (FRR). |
·
Set an IPv4 backup link for FRR: ·
Set an IPv6 backup link for FRR: |
By default, no backup link is set for FRR. |
Configuring the continue clause
Follow these guidelines when you configure the continue clause to combine multiple nodes:
· If you configure an apply clause that sets different attribute values on all the nodes, the apply clause of the node configured most recently takes effect.
· If you configure the following apply clauses on all the nodes, the apply clause of each node takes effect:
? apply as-path without the replace keyword.
? apply cost with the + or – keyword.
? apply community with the additive keyword.
? apply extcommunity with the additive keyword.
· The apply comm-list delete clause configured on the current node cannot delete the community attributes set by the apply community clauses of the preceding nodes.
To configure the continue clause:
Step |
Command |
Remarks |
1. Enter system view. |
system-view |
N/A |
2. Enter routing policy node view. |
route-policy route-policy-name { deny | permit } node node-number |
N/A |
3. Specify the next node to be matched. |
By default, no continue clause is configured. The specified next node must have a larger number than the current node. |
Displaying and maintaining the routing policy
Execute display commands in any view and reset commands in user view.
Task |
Command |
Display BGP AS path list information. |
display ip as-path [ as-path-number ] |
Display BGP community list information. |
display ip community-list [ basic-community-list-number | adv-community-list-number | name comm-list-name ] |
Display BGP extended community list information. |
display ip extcommunity-list [ ext-comm-list-number ] |
Display IPv4 prefix list statistics. |
display ip prefix-list [ name prefix-list-name ] |
Display IPv6 prefix list statistics. |
display ipv6 prefix-list [ name prefix-list-name ] |
Display routing policy information. |
display route-policy [ name route-policy-name ] |
Clear IPv4 prefix list statistics. |
reset ip prefix-list [ prefix-list-name ] |
Clear IPv6 prefix list statistics. |
reset ipv6 prefix-list [ prefix-list-name ] |
Routing policy configuration examples
Routing policy configuration example for IPv4 route redistribution
Network requirements
As shown in Figure 112, Switch B exchanges routing information with Switch A by using OSPF and with Switch C by using IS-IS.
On Switch B, enable route redistribution from IS-IS to OSPF. Use a routing policy to set the cost of route 172.17.1.0/24 to 100 and the tag of route 172.17.2.0/24 to 20.
Configuration procedure
1. Specify IP addresses for interfaces. (Details not shown.)
2. Configure IS-IS:
# Configure Switch C.
<SwitchC> system-view
[SwitchC] isis
[SwitchC-isis-1] is-level level-2
[SwitchC-isis-1] network-entity 10.0000.0000.0001.00
[SwitchC-isis-1] quit
[SwitchC] interface vlan-interface 200
[SwitchC-Vlan-interface200] isis enable
[SwitchC-Vlan-interface200] quit
[SwitchC] interface vlan-interface 201
[SwitchC-Vlan-interface201] isis enable
[SwitchC-Vlan-interface201] quit
[SwitchC] interface vlan-interface 202
[SwitchC-Vlan-interface202] isis enable
[SwitchC-Vlan-interface202] quit
[SwitchC] interface vlan-interface 203
[SwitchC-Vlan-interface203] isis enable
[SwitchC-Vlan-interface203] quit
# Configure Switch B.
<SwitchB> system-view
[SwitchB] isis
[SwitchB-isis-1] is-level level-2
[SwitchB-isis-1] network-entity 10.0000.0000.0002.00
[SwitchB-isis-1] quit
[SwitchB] interface vlan-interface 200
[SwitchB-Vlan-interface200] isis enable
[SwitchB-Vlan-interface200] quit
3. Configure OSPF and route redistribution:
# Configure OSPF on Switch A.
<SwitchA> system-view
[SwitchA] ospf
[SwitchA-ospf-1] area 0
[SwitchA-ospf-1-area-0.0.0.0] network 192.168.1.0 0.0.0.255
[SwitchA-ospf-1-area-0.0.0.0] quit
[SwitchA-ospf-1] quit
# On Switch B, configure OSPF and enable route redistribution from IS-IS to OSPF.
[SwitchB] ospf
[SwitchB-ospf-1] area 0
[SwitchB-ospf-1-area-0.0.0.0] network 192.168.1.0 0.0.0.255
[SwitchB-ospf-1-area-0.0.0.0] quit
[SwitchB-ospf-1] import-route isis 1
[SwitchB-ospf-1] quit
# Display the OSPF routing table on Switch A to view redistributed routes.
[SwitchA] display ospf routing
OSPF Process 1 with Router ID 192.168.1.1
Routing Tables
Routing for Network
Destination Cost Type NextHop AdvRouter Area
192.168.1.0/24 1 Stub 192.168.1.1 192.168.1.1 0.0.0.0
Routing for ASEs
Destination Cost Type Tag NextHop AdvRouter
172.17.1.0/24 1 Type2 1 192.168.1.2 192.168.2.2
172.17.2.0/24 1 Type2 1 192.168.1.2 192.168.2.2
172.17.3.0/24 1 Type2 1 192.168.1.2 192.168.2.2
Total Nets: 4
Intra Area: 1 Inter Area: 0 ASE: 3 NSSA: 0
4. Configure filtering lists:
# Configure IPv4 basic ACL 2002 to permit route 172.17.2.0/24.
[SwitchB] acl basic 2002
[SwitchB-acl-ipv4-basic-2002] rule permit source 172.17.2.0 0.0.0.255
[SwitchB-acl-ipv4-basic-2002] quit
# Configure IP prefix list prefix-a to permit route 172.17.1.0/24.
[SwitchB] ip prefix-list prefix-a index 10 permit 172.17.1.0 24
5. Configure a routing policy.
[SwitchB] route-policy isis2ospf permit node 10
[SwitchB-route-policy-isis2ospf-10] if-match ip address prefix-list prefix-a
[SwitchB-route-policy-isis2ospf-10] apply cost 100
[SwitchB-route-policy-isis2ospf-10] quit
[SwitchB] route-policy isis2ospf permit node 20
[SwitchB-route-policy-isis2ospf-20] if-match ip address acl 2002
[SwitchB-route-policy-isis2ospf-20] apply tag 20
[SwitchB-route-policy-isis2ospf-20] quit
[SwitchB] route-policy isis2ospf permit node 30
[SwitchB-route-policy-isis2ospf-30] quit
6. Apply the routing policy to route redistribution:
# On Switch B, enable route redistribution from IS-IS to OSPF and apply the routing policy.
[SwitchB] ospf
[SwitchB-ospf-1] import-route isis 1 route-policy isis2ospf
[SwitchB-ospf-1] quit
# Display the OSPF routing table on Switch A.
[SwitchA] display ospf routing
OSPF Process 1 with Router ID 192.168.1.1
Routing Tables
Routing for Network
Destination Cost Type NextHop AdvRouter Area
192.168.1.0/24 1 Transit 192.168.1.1 192.168.1.1 0.0.0.0
Routing for ASEs
Destination Cost Type Tag NextHop AdvRouter
172.17.1.0/24 100 Type2 1 192.168.1.2 192.168.2.2
172.17.2.0/24 1 Type2 20 192.168.1.2 192.168.2.2
172.17.3.0/24 1 Type2 1 192.168.1.2 192.168.2.2
Total Nets: 4
Intra Area: 1 Inter Area: 0 ASE: 3 NSSA: 0
The output shows that the cost of route 172.17.1.0/24 is 100 and the tag of route 172.17.2.0/24 is 20.
Routing policy configuration example for IPv6 route redistribution
Network requirements
As shown in Figure 113:
· Run RIPng on Switch A and Switch B.
· Configure three static routes on Switch A.
· On Switch A, apply a routing policy to redistribute static routes 20::/32 and 40::/32 and deny route 30::/32.
Configuration procedure
1. Configure Switch A:
# Configure IPv6 addresses for VLAN-interface 100 and VLAN-interface 200.
<SwitchA> system-view
[SwitchA] interface vlan-interface 100
[SwitchA-Vlan-interface100] ipv6 address 10::1 32
[SwitchA-Vlan-interface100] quit
[SwitchA] interface vlan-interface 200
[SwitchA-Vlan-interface200] ipv6 address 11::1 32
[SwitchA-Vlan-interface200] quit
# Enable RIPng on VLAN-interface 100.
[SwitchA] interface vlan-interface 100
[SwitchA-Vlan-interface100] ripng 1 enable
[SwitchA-Vlan-interface100] quit
# Configure three static routes with next hop 11::2, and make sure the static routes are active.
[SwitchA] ipv6 route-static 20:: 32 11::2
[SwitchA] ipv6 route-static 30:: 32 11::2
[SwitchA] ipv6 route-static 40:: 32 11::2
# Configure a routing policy.
[SwitchA] ipv6 prefix-list a index 10 permit 30:: 32
[SwitchA] route-policy static2ripng deny node 0
[SwitchA-route-policy-static2ripng-0] if-match ipv6 address prefix-list a
[SwitchA-route-policy-static2ripng-0] quit
[SwitchA] route-policy static2ripng permit node 10
[SwitchA-route-policy-static2ripng-10] quit
# Enable RIPng and apply the routing policy to static route redistribution.
[SwitchA] ripng
[SwitchA-ripng-1] import-route static route-policy static2ripng
2. Configure Switch B:
# Configure the IPv6 address for VLAN-interface 100.
<SwitchB> system-view
[SwitchB] interface vlan-interface 100
[SwitchB-Vlan-interface100] ipv6 address 10::2 32
# Enable RIPng.
[SwitchB] ripng
[SwitchB-ripng-1] quit
# Enable RIPng on VLAN-interface 100.
[SwitchB] interface vlan-interface 100
[SwitchB-Vlan-interface100] ripng 1 enable
[SwitchB-Vlan-interface100] quit
Verifying the configuration
# Display the RIPng routing table on Switch B.
[SwitchB] display ripng 1 route
Route Flags: A - Aging, S - Suppressed, G - Garbage-collect
----------------------------------------------------------------
Peer FE80::7D58:0:CA03:1 on Vlan-interface 100
Destination 20::/32,
via FE80::7D58:0:CA03:1, cost 1, tag 0, A, 8 secs
Destination 40::/32,
via FE80::7D58:0:CA03:1, cost 1, tag 0, A, 3 secs
Local route
Destination 10::/32,
via ::, cost 0, tag 0, DOF
Numerics
4-byte
BGP AS number suppression, 262
BGP 6PE configuration, 292
BGP 6PE optional capabilities, 293
IPv6 BGP 6PE configuration, 347
A
ABR
OSPF route summarization, 78
OSPF router type, 67
OSPF summary network discard route, 81
OSPFv3 route summarization, 406
ACL
routing policy, 476
action
IPv6 PBR node action, 469
PBR node, 361
adding
OSPF DD packet interface MTU, 89
address
IS-IS area, 134
IS-IS format, 133
IS-IS NSAP format, 133
IS-IS routing method, 134
MP-BGP address family, 200
adjacency
OSPF BDR, 69
OSPF DR, 69
OSPFv3 area configuration (NSSA), 427
OSPFv3 area configuration (stub), 423
OSPFv3 BFD configuration, 441
OSPFv3 configuration, 400, 401, 423
OSPFv3 DR election configuration, 429
OSPFv3 GR configuration, 439
OSPFv3 route redistribution, 432
advertising
BGP COMMUNITY configuration, 278
BGP COMMUNITY NO_ADVERTISE path attribute, 191
BGP configuration, 191, 203
BGP default route (peer/peer group)(IPv4), 228
BGP default route (peer/peer group)(IPv6), 228
BGP fake AS number (IPv4), 251
BGP fake AS number (IPv6), 251
BGP optimal route (IPv4 unicast), 227
BGP optimal route (IPv6 unicast), 227
BGP route advertisement rules, 195
BGP route generation, 221
IPv4 BGP basic configuration, 300
IPv4 BGP BFD configuration, 326
IPv4 BGP COMMUNITY configuration, 313
IPv4 BGP confederation, 318
IPv4 BGP configuration, 300
IPv4 BGP GR configuration, 325
IPv4 BGP load balancing configuration, 310
IPv4 BGP path selection, 322
IPv4 BGP route reflector configuration, 316
IPv4 BGP route summarization, 307
IPv4 BGP+IGP route redistribution, 304
IPv4 multicast BGP configuration, 334
IPv6 BGP basic configuration, 341
IPv6 BGP BFD configuration, 350
IPv6 BGP configuration, 341
IPv6 BGP route reflector configuration, 344
IS-IS default route, 145
OSPF configuration, 64, 70
OSPF host route, 83
OSPF route summarization configuration, 108
RIP default route, 30
RIP on interface, 27
RIP summary route advertisement configuration, 48
RIPng default route, 382
RIPv2 summary route, 29
applying
IPv6 PBR apply clause, 467
PBR apply clause, 358
routing policy apply clause, 476, 481
area
excluding interfaces in an OSPF area from the base topology, 83
IS-IS, 135
IS-IS area address, 134
IS-IS authentication (area), 158
OSPF area, 74
OSPF area configuration (NSSA), 75, 113
OSPF area configuration (stub), 74, 111
OSPF areas, 65
OSPF authentication (area), 88
OSPF backbone, 66
OSPF network type, 76
OSPF NSSA area, 67
OSPF stub area, 66
OSPF totally NSSA area, 67
OSPF totally stub area, 66
OSPF virtual link, 75
OSPFv3 area configuration (NSSA), 403, 427
OSPFv3 area configuration (stub), 403, 423
OSPFv3 area parameter, 403
OSPFv3 virtual link, 404
AS
BGP 4-byte AS number suppression, 262
BGP AS number substitution, 252
BGP confederation, 282
BGP confederation compatibility, 283
BGP configuration, 191, 203
BGP fake AS number advertisement, 251
BGP first AS number of EBGP route update ignore, 255
BGP link state (LS) AS number, 296
BGP local AS number appearance, 250
BGP MED attribute, 244
BGP MED route comparison (confederation peers), 247
BGP MED route comparison (diff ASs), 245
BGP MED route comparison (per-AS), 245
BGP path AS_PATH attribute, 191
BGP path AS_SEQUENCE attribute, 191
BGP path AS_SET attribute, 191
BGP private AS number removal, 254
IPv4 BGP basic configuration, 300
IPv4 BGP BFD configuration, 326
IPv4 BGP COMMUNITY configuration, 313
IPv4 BGP confederation, 318
IPv4 BGP configuration, 300
IPv4 BGP FRR configuration, 330
IPv4 BGP GR configuration, 325
IPv4 BGP load balancing configuration, 310
IPv4 BGP path selection, 322
IPv4 BGP route reflector configuration, 316
IPv4 BGP route summarization, 307
IPv4 BGP+IGP route redistribution, 304
IPv4 multicast BGP configuration, 334
IPv6 BGP basic configuration, 341
IPv6 BGP BFD configuration, 350
IPv6 BGP configuration, 341
IPv6 BGP FRR configuration, 353
IPv6 BGP route reflector configuration, 344
IS-IS authentication configuration, 177
IS-IS basic configuration, 140
IS-IS basics configuration, 165
IS-IS configuration, 133, 139, 165
IS-IS DIS election configuration, 169
IS-IS route redistribution, 173
OSPF areas, 65
OSPF AS External LSA, 64
routing policy AS_PATH list, 476, 478
AS_PATH
BGP attribute, 250
BGP attribute ignore, 251
ASBR
OSPF ASBR summary LSA, 64
OSPF redistributed route summarization, 79
OSPF router type, 67
OSPF summary network discard route, 81
OSPFv3 redistributed route summarization, 406
assigning
IPv6 IS-IS route convergence priority, 450
ATT
IS-IS ATT bit, 153
IS-IS ATT bit default route calculation, 153
IS-IS ATT bit Level-1 LSP, 153
attribute
BGP AS_PATH attribute ignore, 251
BGP IGP metrics ignore, 255
BGP MED attribute, 244
BGP path AS_PATH, 191
BGP path COMMUNITY, 191
BGP path LOCAL_PREF, 191
BGP path MED, 191
BGP path NEXT_HOP, 191
BGP path ORIGIN, 191
IPv4 BGP COMMUNITY configuration, 313
MP-BGP MP_REACH_NLRI extended attribute, 200
MP-BGP MP_UNREACH_NLRI extended attribute, 200
authenticating
BGP peer keychain authentication, 264
BGP peer MD5 authentication, 263
IS-IS authentication (area), 158
IS-IS authentication (neighbor relationship), 158
IS-IS authentication (routing domain), 159
IS-IS authentication configuration, 177
IS-IS network security enhancement, 158
OSPF configuration, 88
OSPFv3 configuration, 416
RIPv2 message authentication configuration, 34
auto
BGP route summarization (automatic)(IPv4), 224
IPv6 IS-IS automatic link cost calculation, 449
IPv6 IS-IS FRR automatic backup next hop (LFA calculation), 454
IS-IS automatic cost calculation, 143
automatic
RIPv2 automatic route summarization enable, 29
B
backbone
OSPF backbone area, 66
OSPF router type, 67
backing up
IP routing route backup, 3
bandwidth
OSPF reference value, 80
BDR
OSPF, 69
OSPF election, 70
BFD
BGP configuration, 288
IPv4 BGP BFD configuration configuration, 326
IPv6 BGP BFD configuration configuration, 350
IPv6 IS-IS BFD configuration, 452, 461
IPv6 IS-IS FRR BFD, 454
IPv6 static route BFD configuration, 368
IPv6 static route BFD control mode (direct next hop), 369
IPv6 static route BFD control mode (indirect next hop), 369
IPv6 static route BFD echo mode (single hop), 369
IPv6 static routing BFD (direct next hop)(on switch), 372
IPv6 static routing BFD (indirect next hop)(on switch), 375
IS-IS BFD, 161
IS-IS BFD configuration, 184
IS-IS FRR BFD enable (control packet mode), 163
IS-IS FRR BFD enable (echo packet mode), 163
OSPF BFD configuration, 126
OSPF detection configuration (bidirectional control), 99
OSPF detection configuration (single-hop echo), 100
OSPF FRR configuration, 101
OSPF PIC BFD, 94
OSPFv3 BFD configuration, 419, 441
OSPFv3 FRR configuration, 421
RIP BFD configuration, 38
RIP BFD configuration (bidirectional control detection), 40
RIP BFD configuration (bidirectional detection/control packet mode), 58
RIP BFD configuration (single-hop echo detection), 53
RIP BFD configuration (single-hop echo detection/neighbor), 39
RIP BFD configuration (single-hop echo detection/specific destination), 39, 56
RIP FRR BFD enable, 41
RIPng FRR BFD enable, 388
static routing BFD bidirectional control mode (direct next hop), 10
static routing BFD bidirectional control mode (indirect next hop), 10
static routing BFD configuration, 10
static routing BFD configuration (direct next hop), 15
static routing BFD configuration (indirect next hop), 18
static routing BFD echo mode (single-hop), 11
4-byte AS number suppression, 262
6PE configuration, 292, 347
6PE optional capabilities, 293
advertising OSPF link state information to BGP, 102
AS number substitution, 252
AS_PATH attribute configuration, 250
AS_PATH attribute ignore, 251
basic configuration, 206
BFD configuration, 288
COMMUNITY configuration, 278
confederation compatibility, 283
confederation configuration, 282
configuration, 191, 203
configuration views, 201
default local preference configuration, 242
default route advertisement (peer/peer group), 228
dynamic peer configuration, 209
EBGP direct connections after link failure, 261
EBGP peer protection (low memory exemption), 274
EBGP session establishment (multiple hop), 260
enable, 206
fake AS number advertisement, 251
first AS number of EBGP route update ignore, 255
FRR configuration, 289
GR configuration, 283
GTSM configuration, 267
IGP route redistribution, 223
IPv4 basic configuration, 300
IPv4 BFD configuration, 326
IPv4 COMMUNITY configuration, 313
IPv4 confederation configuration, 318
IPv4 dynamic peer configuration, 337
IPv4 FRR configuration, 330
IPv4 GR configuration, 325
IPv4 IGP route redistribution, 304
IPv4 load balancing configuration, 310
IPv4 multicast configuration, 334
IPv4 path selection configuration, 322
IPv4 route reflector configuration, 316
IPv4 route summarization, 307
IPv6 basic configuration, 341
IPv6 BFD configuration, 350
IPv6 FRR configuration, 353
IPv6 route reflector configuration, 344
keepalive interval+hold time configuration, 258
large scale network management, 197
large-scale network configuration, 278
link state (LS) AS number, 296
link state (LS) route reflection, 295
link state (LS) router ID, 296
load balancing, 196
load balancing configuration, 265
local AS number appearance, 250
local network injection, 221
LS configuration, 295, 339
manual soft reset configuration, 272
MED attribute configuration, 244
message types, 191
MP-BGP, 200
MP-BGP address family, 200
MP-BGP extended attributes, 200
MPLS local label update delay, 275
multi-instance, 201
network optimization, 258
NEXT_HOP attribute, 248
nonstop routing (NSR) configuration, 284
optimal route advertisement, 227
optimal route selection disable for labeled routes, 277
ORIGINATOR_ID attribute ignore, 281
outgoing packet DSCP value, 276
path attributes, 191
path selection control, 239
peer, 191
peer configuration, 207
peer configuration (IPv4 unicast address), 207
peer configuration (IPv6 unicast address), 208
peer group configuration, 211
peer keychain authentication, 264
peer MD5 authentication, 263
per-prefix label allocation enable, 277
private AS number removal, 254
protocols and standards, 203
received route preferred value, 239
route advertisement rules, 195
route dampening configuration, 238
route distribution control, 224
route filtering policy, 231
route flapping logging, 286
route generation, 221
route preference configuration, 241
route reception control, 224
route recursion, 196
route reflection, 280
route reflector configuration, 280
route refresh enable, 269
route selection, 195, 196
route summarization, 224
route update delay, 237
route update interval, 259
route update save, 270
routes received limit (peer/peer group), 230
routing policy AS_PATH list, 476
routing policy COMMUNITY list, 476
session establishment disable, 266
session state change logging, 285
SNMP notification enable, 285
soft reset configuration, 268
SoO attribute configuration, 256
speaker, 191
suboptimal route flush to RIB, 276
TCP connection source address, 220
troubleshoot, 357
troubleshoot peer connection state, 357
tuning network, 258
bidirectional
IPv6 static route BFD control mode (direct next hop), 369
IPv6 static route BFD control mode (indirect next hop), 369
IPv6 static route BFD echo mode (single hop), 369
OSPF BFD detection configuration (bidirectional control), 99
RIP BFD configuration (bidirectional control detection), 40
RIP BFD configuration (bidirectional detection/control packet mode), 58
static routing BFD bidirectional control mode (direct next hop), 10
static routing BFD bidirectional control mode (indirect next hop), 10
Border Gateway Protocol. Use BGP
broadcast
IS-IS network type, 136
OSPF interface network type, 76
OSPF network type, 69, 76
OSPFv3 network type, 404
OSPFv3 network type (interface), 405
C
calculating
IPv6 IS-IS SPF calculation interval, 451
IS-IS ATT bit default route calculation, 153
IS-IS SPF calculation interval, 151
OSPF FRR backup next hop calculation (LFA algorithm), 101
OSPF interface cost, 80
OSPF route calculation, 68
OSPF SPF calculation interval, 85
OSPFv3 FRR backup next hop calculation (LFA algorithm), 420
OSPFv3 SPF calculation interval, 411
checking
OSPFv3 DD packet ignore MTU check, 412
circuit
IS-IS IS+circuit level, 141
classless inter-domain routing. Use CIDR
clearing
IPv4 BGP information, 299
IPv6 BGP information, 299
CLNP
IS-IS configuration, 139
CLV (IS-IS PDU), 138
COMMUNITY
BGP COMMUNITY configuration, 278
IPv4 BGP COMMUNITY configuration, 313
community
routing policy extended community list, 478
routing policy list, 476
COMMUNITY
BGP COMMUNITY path attribute, 191
routing policy COMMUNITY list, 478
community
routing policy extended community list, 476
comparing
BGP MED route comparison (confederation peers), 247
BGP MED route comparison (diff ASs), 245
BGP MED route comparison (per-AS), 245
confederating
BGP confederation, 282
BGP confederation compatibility, 283
BGP MED route comparison (confederation peers), 247
IPv4 BGP confederation, 318
configuring
BGP, 191, 203
BGP 6PE, 292
BGP 6PE basics, 292
BGP 6PE optional capabilities, 293
BGP AS number substitution (IPv4), 252
BGP AS number substitution (IPv6), 252
BGP AS_PATH attribute, 250
BGP basics, 206
BGP BFD (IPv4), 288
BGP BFD (IPv6), 288
BGP COMMUNITY (IPv4), 278
BGP COMMUNITY (IPv6), 278
BGP confederation, 282
BGP confederation compatibility, 283
BGP default local preference (IPv4), 242
BGP default local preference (IPv6), 242
BGP dynamic peer (IPv4 multicast address), 210
BGP dynamic peer (IPv4 unicast address), 209
BGP dynamic peer (IPv6 unicast address), 210
BGP FRR (IPv4 unicast address), 289
BGP FRR (IPv6 unicast address), 289
BGP GR, 283
BGP GTSM (IPv4), 267
BGP GTSM (IPv6), 267
BGP keepalive interval+hold time, 258
BGP large-scale network, 278
BGP link state (LS) route reflection, 295
BGP load balancing (IPv4), 265
BGP load balancing (IPv6), 265
BGP LS, 295, 339
BGP manual soft reset (IPv4), 272
BGP manual soft reset (IPv6), 272
BGP MED attribute, 244
BGP MED default value (IPv4), 244
BGP MED default value (IPv6), 244
BGP MPLS local label update delay, 275
BGP NEXT_HOP attribute (IPv4), 248
BGP NEXT_HOP attribute (IPv6), 248
BGP NSR, 284
BGP peer (IPv4 multicast address), 209
BGP peer (IPv4 unicast address), 207
BGP peer (IPv6 unicast address), 208
BGP route dampening (IPv4), 238
BGP route dampening (IPv6), 238
BGP route distribution filtering policy (IPv4), 231
BGP route distribution filtering policy (IPv6), 231
BGP route filtering policy, 231
BGP route preference (IPv4), 241
BGP route preference (IPv6), 241
BGP route reception filtering policy (IPv4), 235
BGP route reception filtering policy (IPv6), 235
BGP route reflection, 280
BGP route reflector (IPv4), 280
BGP route reflector (IPv6), 280
BGP route summarization (automatic )(IPv4), 224
BGP route summarization (manual)(IPv4), 225
BGP route summarization (manual)(IPv6), 225
BGP route update delay, 237
BGP route update interval (IPv4), 259
BGP route update interval (IPv6), 259
BGP soft reset, 268
BGP SoO attribute (IPv4), 256
BGP SoO attribute (IPv6), 256
EBGP peer group (IPv4 multicast address), 213
EBGP peer group (IPv4 unicast address), 213
EBGP peer group (IPv6 multicast address), 213
EBGP peer group (IPv6 unicast address), 213
IBGP peer group (IPv4 multicast address), 211
IBGP peer group (IPv4 unicast address), 211
IBGP peer group (IPv6 multicast address), 211
IBGP peer group (IPv6 unicast address), 211
interface outbound PBR, 363
interface PBR, 362
interface PBR (packet type-based), 365
IP routing, 1
IP routing inter-protocol FRR, 6
IP routing IPv4 RIB inter-protocol FRR, 6
IP routing IPv6 RIB inter-protocol FRR, 6
IP routing RIB NSR, 5
IPv4 BGP, 300
IPv4 BGP basics, 300
IPv4 BGP BFD, 326
IPv4 BGP COMMUNITY, 313
IPv4 BGP confederation, 318
IPv4 BGP dynamic peer, 337
IPv4 BGP FRR, 330
IPv4 BGP GR, 325
IPv4 BGP load balancing, 310
IPv4 BGP path selection, 322
IPv4 BGP route reflector, 316
IPv4 BGP route summarization, 307
IPv4 BGP+IGP route redistribution, 304
IPv4 multicast BGP, 334
IPv4 RIB NSR, 5
IPv6 BGP, 341
IPv6 BGP 6PE configuration, 347
IPv6 BGP basics, 341
IPv6 BGP BFD, 350
IPv6 BGP FRR, 353
IPv6 BGP route reflector, 344
IPv6 default route, 378
IPv6 IS-IS, 447, 456
IPv6 IS-IS basics, 447, 456
IPv6 IS-IS BFD, 452, 461
IPv6 IS-IS FRR, 453, 463
IPv6 IS-IS FRR (routing policy), 454
IPv6 IS-IS FRR automatic backup next hop (LFA calculation), 454
IPv6 IS-IS global cost, 449
IPv6 IS-IS interface cost, 449
IPv6 IS-IS interface tag value, 451
IPv6 IS-IS link cost, 449
IPv6 IS-IS route control, 448
IPv6 PBR, 467, 468, 470, 471
IPv6 PBR interface, 470
IPv6 PBR interface (packet type-based), 473
IPv6 PBR local, 470
IPv6 PBR local (packet type-based), 471
IPv6 PBR node action, 469
IPv6 PBR policy, 469
IPv6 RIB NSR, 5
IPv6 static route, 368
IPv6 static route BFD, 368
IPv6 static route BFD control mode (direct next hop), 369
IPv6 static route BFD control mode (indirect next hop), 369
IPv6 static route BFD echo mode (single hop), 369
IPv6 static routing, 368
IPv6 static routing (on switch), 370
IPv6 static routing basics (on switch), 370
IPv6 static routing BFD (direct next hop)(on switch), 372
IPv6 static routing BFD (indirect next hop)(on switch), 375
IS-IS, 133, 139, 165
IS-IS ATT bit, 153
IS-IS ATT bit default route calculation, 153
IS-IS authentication (area), 158
IS-IS authentication (neighbor relationship), 158
IS-IS authentication (routing domain), 159
IS-IS authentication configuration, 177
IS-IS basics, 140, 165
IS-IS BFD, 161, 184
IS-IS DIS election, 169
IS-IS ECMP routes max, 144
IS-IS FRR, 161, 187
IS-IS FRR (routing policy), 162
IS-IS FRR backup next hop (LFA calculation), 162
IS-IS global cost, 143
IS-IS GR, 159, 180
IS-IS interface cost, 143
IS-IS interface DIS priority, 148
IS-IS interface P2P network type, 141
IS-IS interface tag value, 153
IS-IS link cost, 142
IS-IS LSP parameters, 149
IS-IS LSP timer, 149
IS-IS LSP-calculated route filtering, 146
IS-IS network management, 156
IS-IS NSR, 160, 181
IS-IS PIC, 157
IS-IS redistributed route filtering, 146
IS-IS route control, 142
IS-IS route convergence priority, 152
IS-IS route filtering, 145
IS-IS route leaking, 146
IS-IS route redistribution, 145, 173
IS-IS route summarization, 144
IS-IS system ID > host name mapping, 154
IS-IS system ID > host name mapping (dynamic), 154
IS-IS system ID > host name mapping (static), 154
local PBR, 362
local PBR (packet type-based), 364
maximum number of OSPFv3 logs, 416
OSPF, 64, 70, 104
OSPF area, 74
OSPF area (NSSA), 75, 113
OSPF area (stub), 74, 111
OSPF authentication (area), 88
OSPF authentication (interface), 88
OSPF basics, 104
OSPF BFD, 126
OSPF BFD detection (bidirectional control), 99
OSPF BFD detection (single-hop echo), 100
OSPF DR election, 115
OSPF FRR, 100, 129
OSPF FRR backup next hop (routing policy), 101
OSPF FRR backup next hop calculation (LFA algorithm), 101
OSPF FRR BFD, 101
OSPF GR, 97, 121
OSPF GR helper (IETF), 98
OSPF GR helper (non-IETF), 98
OSPF GR restarter, 97
OSPF GR restarter (IETF), 97
OSPF GR restarter (non-IETF), 97
OSPF GTSM, 96
OSPF interface cost, 80
OSPF interface network type (broadcast), 76
OSPF interface network type (NBMA), 76
OSPF interface network type (P2MP), 77
OSPF interface network type (P2P), 78
OSPF network management, 91
OSPF network type, 76
OSPF NSR, 99, 124
OSPF PIC, 94
OSPF PIC BFD, 94
OSPF prefix priority, 93
OSPF prefix suppression (interface), 93
OSPF prefix suppression (OSPF process), 93
OSPF received route filtering, 79
OSPF redistributed route default parameters, 83
OSPF redistributed route summarization (on ASBR), 79
OSPF route control, 78
OSPF route redistribution, 106
OSPF route summarization, 108
OSPF route summarization (on ABR), 78
OSPF stub router, 87
OSPF summary network discard route, 81
OSPF Type-3 LSA filtering, 80
OSPF virtual link, 75, 119
OSPFv3, 400, 401
OSPFv3 area (NSSA), 403, 427
OSPFv3 area (stub), 403, 423
OSPFv3 area parameter, 403
OSPFv3 authentication, 416
OSPFv3 authentication (area), 416
OSPFv3 authentication (interface), 417
OSPFv3 BFD, 419
OSPFv3 BFD configuration, 441
OSPFv3 configuration, 423
OSPFv3 DR election, 429
OSPFv3 FRR, 419, 444
OSPFv3 FRR backup next hop (routing policy), 421
OSPFv3 FRR backup next hop calculation (LFA algorithm), 420
OSPFv3 FRR BFD, 421
OSPFv3 GR, 417, 439
OSPFv3 GR helper, 418
OSPFv3 GR restarter, 417
OSPFv3 Inter-Area-Prefix LSA filtering, 407
OSPFv3 interface cost, 407
OSPFv3 interface DR priority, 412
OSPFv3 LSU transmit rate, 414
OSPFv3 NBMA neighbor, 405
OSPFv3 network management, 413
OSPFv3 network type, 404
OSPFv3 network type (interface), 405
OSPFv3 NSR, 418, 440
OSPFv3 P2MP neighbor, 405
OSPFv3 preference, 408
OSPFv3 prefix suppression (interface), 416
OSPFv3 prefix suppression (OSPFv3 process), 415
OSPFv3 received route filtering, 407
OSPFv3 redistributed route tag, 410
OSPFv3 route control, 406
OSPFv3 route redistribution, 432
OSPFv3 route redistribution (another routing protocol), 409
OSPFv3 route redistribution (default route), 409
OSPFv3 route summarization, 435
OSPFv3 route summarization (on ABR), 406
OSPFv3 route summarization (on ASBR), 406
OSPFv3 stub router, 414
OSPFv3 virtual link, 404
PBR, 358, 360, 362, 364
PBR node action, 361
PBR policy, 360
RIP, 24, 25, 42
RIP additional routing metric, 28
RIP basics, 26, 42
RIP BFD, 38
RIP BFD (bidirectional control detection), 40
RIP BFD (bidirectional detection/control packet mode), 58
RIP BFD (single-hop echo detection), 53
RIP BFD (single-hop echo detection/neighbor), 39
RIP BFD (single-hop echo detection/specific destination), 39, 56
RIP FRR, 40, 61
RIP GR, 37, 51
RIP interface additional metric, 47
RIP network management, 36
RIP NSR, 52
RIP packet send rate, 36
RIP poison reverse, 33
RIP received/redistributed route filtering, 30
RIP route control, 28
RIP route redistribution, 31, 45
RIP summary route advertisement, 48
RIP timers, 32
RIP version, 27
RIPng, 379, 380, 389
RIPng basics, 380, 389
RIPng FRR, 387, 388, 397
RIPng GR, 386, 394
RIPng NSR, 387, 395
RIPng packet send rate, 385
RIPng packet zero field check, 384
RIPng poison reverse, 384
RIPng received/redistributed route filtering, 382
RIPng route control, 381
RIPng route redistribution, 383, 392
RIPng route summarization, 381
RIPng routing metric, 381
RIPng split horizon, 384
RIPv2 message authentication, 34
RIPv2 route summarization, 29
routing policy, 476, 479, 483
routing policy (IPv4 route redistribution), 483
routing policy (IPv6 route redistribution), 486
routing policy apply clause, 481
routing policy AS_PATH list, 478
routing policy COMMUNITY list, 478
routing policy continue clause, 482
routing policy extended community list, 478
routing policy filter, 477
routing policy if-match clause, 479
routing policy IPv4 prefix list, 477
routing policy IPv6 prefix list, 477
static routing, 9, 9, 14
static routing basics, 14
static routing BFD, 10
static routing BFD (direct next hop), 15
static routing BFD (indirect next hop), 18
static routing BFD bidirectional control mode (direct next hop), 10
static routing BFD bidirectional control mode (indirect next hop), 10
static routing BFD echo mode (single-hop), 11
static routing default route, 23
static routing FRR, 12, 20
static routing FRR (auto select backup next hop), 13
static routing FRR BFD echo packet mode, 13
static routing FRR(backup next hop), 12
connecting
BGP TCP connection source address, 220
EBGP direct connections after link failure, 261
continue clause (routing policy), 476, 482
controlling
BGP path selection, 239
BGP route distribution, 224
BGP route reception, 224
IPv6 IS-IS route control, 448
IPv6 IS-IS SPF calculation interval, 451
IPv6 static route BFD control mode (direct next hop), 369
IPv6 static route BFD control mode (indirect next hop), 369
IS-IS route control, 142
IS-IS SPF calculation interval, 151
OSPF route control, 78
OSPFv3 route control, 406
RIP additional routing metric configuration, 28
RIP BFD configuration (bidirectional detection/control packet mode), 58
RIP interface advertisement, 27
RIP interface reception, 27, 27
RIP route control configuration, 28
RIPng route control, 381
convergence priority (IPv6 IS-IS), 450
convergence priority (IS-IS), 152
cost
IPv6 IS-IS automatic link cost calculation, 449
IPv6 IS-IS global cost, 449
IPv6 IS-IS interface cost, 449
IPv6 IS-IS link cost, 449
IS-IS automatic cost calculation, 143
IS-IS global cost, 143
IS-IS interface cost, 143
IS-IS link cost, 142
OSPF interface cost, 80
OSPFv3 interface cost, 407
creating
IPv6 PBR node, 469
PBR node, 360
routing policy, 479
CSNP
IS-IS CSNP packet send interval, 148
D
dampening
BGP route dampening, 238
database
OSPF DD packet, 64
DD
OSPFv3 DD packet ignore MTU check, 412
OSPFv3 packet type, 400
dead packet timer (OSPF), 84
default
BGP default local preference, 242
BGP default route advertisement (peer/peer group), 228
BGP MED default value, 244
IPv6 default route configuration, 378
IS-IS default route advertisement, 145
OSPF redistributed route default parameters, 83
OSPFv3 route redistribution (default route), 409
RIP default route advertisement, 30
RIPng default route advertisement, 382
static routing configuration. See under static routing
delaying
BGP MPLS local label update delay, 275
BGP route update delay, 237
OSPFv3 LSA transmission delay, 411
detecting
BGP BFD, 288
OSPF BFD detection configuration (bidirectional control), 99
OSPF BFD detection configuration (single-hop echo), 100
OSPF FRR BFD, 101
OSPFv3 FRR BFD, 421
RIP BFD configuration (bidirectional control detection), 40
RIP BFD configuration (bidirectional detection/control packet mode), 58
RIP BFD configuration (single-hop echo detection), 53
RIP BFD configuration (single-hop echo detection/neighbor), 39
RIP BFD configuration (single-hop echo detection/specific destination), 39, 56
RIP BFD single-hop echo detection, 38
device
BGP LS configuration, 339
interface PBR configuration (packet type-based), 365
IPv4 BGP basic configuration, 300
IPv4 BGP BFD configuration, 326
IPv4 BGP COMMUNITY configuration, 313
IPv4 BGP confederation, 318
IPv4 BGP configuration, 300
IPv4 BGP dynamic peer configuration, 337
IPv4 BGP GR configuration, 325
IPv4 BGP load balancing configuration, 310
IPv4 BGP path selection, 322
IPv4 BGP route reflector configuration, 316
IPv4 BGP route summarization, 307
IPv4 BGP+IGP route redistribution, 304
IPv4 multicast BGP configuration, 334
IPv6 BGP 6PE configuration, 347
IPv6 BGP basic configuration, 341
IPv6 BGP BFD configuration, 350
IPv6 BGP configuration, 341
IPv6 BGP route reflector configuration, 344
IPv6 IS-IS basic configuration, 456
IPv6 IS-IS BFD configuration, 461
IPv6 IS-IS configuration, 456
IPv6 IS-IS FRR configuration, 463
IPv6 PBR interface configuration (packet type-based), 473
IPv6 PBR local configuration (packet type-based), 471
IPv6 static routing (on switch), 370
IPv6 static routing basics (on switch), 370
IPv6 static routing BFD (direct next hop)(on switch), 372
IPv6 static routing BFD (indirect next hop)(on switch), 375
IS-IS authentication configuration, 177
IS-IS basics configuration, 165
IS-IS BFD configuration, 184
IS-IS configuration, 165
IS-IS DIS election configuration, 169
IS-IS FRR configuration, 187
IS-IS GR configuration, 180
IS-IS NSR configuration, 181
IS-IS route redistribution, 173
local PBR configuration (packet type-based), 364
OSPF ABR router type, 67
OSPF area configuration (NSSA), 113
OSPF area configuration (stub), 111
OSPF ASBR router type, 67
OSPF backbone router type, 67
OSPF basic configuration, 104
OSPF BFD configuration, 126
OSPF configuration, 104
OSPF DR election configuration, 115
OSPF FRR configuration, 129
OSPF GR configuration, 121
OSPF internal router type, 67
OSPF NSR configuration, 124
OSPF route redistribution configuration, 106
OSPF route summarization configuration, 108
OSPF stub router, 87
OSPF virtual link configuration, 119
OSPFv3 area configuration (NSSA), 427
OSPFv3 area configuration (stub), 423
OSPFv3 BFD configuration, 441
OSPFv3 configuration, 423
OSPFv3 DR election configuration, 429
OSPFv3 FRR configuration, 444
OSPFv3 GR configuration, 439
OSPFv3 route redistribution, 432
OSPFv3 route summarization, 435
OSPFv3 stub router, 414
RIP basic configuration, 42
RIP BFD configuration (bidirectional detection/control packet mode), 58
RIP BFD configuration (single-hop echo detection), 53
RIP BFD configuration (single-hop echo detection/specific destination), 56
RIP configuration, 42
RIP FRR configuration, 61
RIP GR configuration, 51
RIP interface additional metric configuration, 47
RIP NSR configuration, 52
RIP route redistribution, 45
RIP summary route advertisement configuration, 48
RIPng basic configuration, 389
RIPng configuration, 389
RIPng FRR configuration, 397
RIPng GR configuration, 394
RIPng NSR configuration, 395
RIPng route redistribution, 392
routing policy configuration, 483
routing policy configuration (IPv4 route redistribution), 483
routing policy configuration (IPv6 route redistribution), 486
static routing basic configuration, 14
static routing BFD configuration (direct next hop), 15
static routing BFD configuration (indirect next hop), 18
static routing configuration, 14
static routing FRR configuration, 20
DIS
IS-IS DIS election, 136
IS-IS DIS election configuration, 169
IS-IS interface DIS priority, 148
disabling
BGP optimal route selection for labeled routes, 277
BGP session establishment (IPv4), 266
BGP session establishment (IPv6), 266
IS-IS interface packet send/receive, 148
OSPF interface packet send/receive disable, 87
OSPFv3 interface packet send/receive, 412
RIP host route reception, 30
discard route (OSPF), 81
displaying
BGP, 296
IP routing table, 7
IPv4 BGP, 296
IPv6 BGP, 296
IPv6 IS-IS, 456
IPv6 PBR, 471
IPv6 static routing, 370
IS-IS, 163
OSPF, 102
OSPFv3, 422
PBR, 363
RIP, 41
RIPng, 389
routing policy, 483
static routing, 13
distributing
BGP IGP route redistribution, 223
BGP route distribution control, 224
IP routing extension attribute redistribution, 3
IP routing route redistribution, 3
IPv4 BGP+IGP route redistribution, 304
IS-IS route redistribution, 145
OSPF route redistribution, 82
OSPFv3 route redistribution, 409, 432
RIPng received/redistributed route filtering, 382
RIPng route redistribution, 383, 392
domain
IS-IS authentication (routing domain), 159
IS-IS routing domain, 135
DR
OSPF, 69
OSPF DR election configuration, 115
OSPF election, 70
OSPFv3 DR election configuration, 429
OSPFv3 interface DR priority, 412
DSCP
BGP outgoing packet DSCP value, 276
OSPF packet DSCP value, 90
outgoing OSPF packet DSCP value, 89
DSP (IS-IS area address), 134
dynamic
BGP dynamic peer, 209
IP routing dynamic routing protocols, 2
IS-IS system ID > host name mapping, 154
E
EBGP
BGP confederation, 282
BGP first AS number of route update ignore, 255
BGP private AS number removal from peer/peer group update, 254
direct connections after link failure, 261
peer, 191
peer group configuration (IPv4 multicast address), 213
peer group configuration (IPv4 unicast address), 213
peer group configuration (IPv6 multicast address), 213
peer group configuration (IPv6 unicast address), 213
session establishment (multiple hop), 260
echo
IPv6 static route BFD echo mode (single hop), 369
RIP BFD configuration (bidirectional detection/control packet mode), 58
RIP BFD configuration (single-hop echo detection), 53
RIP BFD configuration (single-hop echo detection/specific destination), 56
RIP BFD single-hop echo detection, 38
static routing BFD echo mode (single-hop), 11
BGP load balancing, 265
IPv4 ECMP enhanced mode, 7
ISIS ECMP routes max, 144
OSPF ECMP routes max, 81
OSPFv3 ECMP route max, 408
RIP ECMP route max number, 33
RIPng ECMP route max, 385
electing
OSPF DR election configuration, 115
OSPFv3 DR election configuration, 429
enabling
advertising OSPF link state information to BGP, 102
BGP, 206
BGP 4-byte AS number suppression (IPv4), 262
BGP 4-byte AS number suppression (IPv6), 262
BGP MED route comparison (confederation peers), 247
BGP MED route comparison (diff ASs), 245
BGP MED route comparison (per-AS), 245
BGP peer keychain authentication (IPv4), 264
BGP peer keychain authentication (IPv6), 264
BGP peer MD5 authentication (IPv4), 263
BGP peer MD5 authentication (IPv6), 263
BGP per-prefix label allocation, 277
BGP route flapping logging (IPv4), 286
BGP route flapping logging (IPv6), 286
BGP route refresh (IPv4), 269
BGP route refresh (IPv6), 269
BGP session state change logging (IPv4), 285
BGP session state change logging (IPv6), 285
BGP SNMP notification, 285
EBGP direct connections after link failure, 261
EBGP session establishment (multiple hop)(IPv4), 260
EBGP session establishment (multiple hop)(IPv6), 260
IPv4 ECMP enhanced mode, 7
IPv6 IS-IS automatic link cost calculation, 449
IPv6 IS-IS FRR BFD, 454
IPv6 IS-IS ISPF, 452
IPv6 IS-IS MTR, 455
IPv6 IS-IS prefix suppression, 452
IS-IS, 141
IS-IS automatic cost calculation, 143
IS-IS FRR BFD (control packet mode), 163
IS-IS FRR BFD (echo packet mode), 163
IS-IS interface hello packet send, 149
IS-IS ISPF, 155
IS-IS LSP flash flooding, 151
IS-IS LSP fragment extension, 151
IS-IS neighbor state change logging, 155
IS-IS PIC, 157
IS-IS PIC BFD, 157
IS-IS prefix suppression, 155
OSPF, 72
OSPF (on interface), 74
OSPF (on network), 73
OSPF ISPF, 92
OSPF PIC, 94
OSPF RFC 1583 compatibility, 90
OSPFv3, 402
OSPFv3 neighbor state change logging, 413
RIP (on interface), 27
RIP (on network), 26
RIP FRR BFD, 41
RIP NSR, 38
RIP poison reverse, 33
RIP split horizon, 33, 33
RIP update source IP address check, 34
RIPng FRR BFD, 388
RIPv1 incoming message zero field check, 34
RIPv2 automatic route summarization, 29
enhancing
IS-IS network security, 158
establishing
BGP session establishment disable, 266
EBGP session establishment (multiple hop), 260
excluding
interfaces in an OSPF area from the base topology, 83
exit overflow interval (OSPF), 89
extending
IS-IS LSP fragment extension, 151
MP-BGP MP_REACH_NLRI extended attribute, 200
MP-BGP MP_UNREACH_NLRI extended attribute, 200
Exterior Gateway Protocol. Use EGP
external
OSPF LSDB external LSAs max, 89
external BGP. Use EGP
F
FIB
IP routing table, 1
filtering
BGP configuration, 191, 203
BGP route distribution filtering policy, 231
BGP route filtering policy, 231
BGP route reception filtering policy, 235
IPv4 BGP basic configuration, 300
IPv4 BGP BFD configuration, 326
IPv4 BGP COMMUNITY configuration, 313
IPv4 BGP confederation, 318
IPv4 BGP configuration, 300
IPv4 BGP FRR configuration, 330
IPv4 BGP GR configuration, 325
IPv4 BGP load balancing configuration, 310
IPv4 BGP path selection, 322
IPv4 BGP route reflector configuration, 316
IPv4 BGP route summarization, 307
IPv4 BGP+IGP route redistribution, 304
IPv6 BGP basic configuration, 341
IPv6 BGP BFD configuration, 350
IPv6 BGP configuration, 341
IPv6 BGP FRR configuration, 353
IPv6 BGP route reflector configuration, 344
IS-IS LSP-calculated routes, 146
IS-IS redistributed routes, 146
IS-IS routes, 145
OSPF outbound LSA (on interface), 95, 99
OSPF outbound LSAs (specified neighbor), 95
OSPF received route filtering, 79
OSPF Type-3 LSA filtering, 80
OSPFv3 Inter-Area-Prefix LSA filtering, 407
OSPFv3 received route filtering, 407
RIP received/redistributed route filtering, 30
RIPng received/redistributed route filtering, 382
routing policy ACLs, 476
routing policy apply clause, 481
routing policy AS_PATH list, 476, 478
routing policy COMMUNITY list, 476, 478
routing policy configuration, 476, 479, 483
routing policy configuration (IPv4 route redistribution), 483
routing policy configuration (IPv6 route redistribution), 486
routing policy continue clause, 482
routing policy creation, 479
routing policy extended community list, 476, 478
routing policy filter configuration, 477
routing policy filters, 476
routing policy if-match clause, 479
routing policy IP prefix list, 477
routing policy prefix list, 476
flapping
BGP route flapping logging, 286
flooding
IS-IS LSP flash flooding, 151
flushing
BGP suboptimal route to RIB, 276
format
IS-IS address format, 133
IS-IS NSAP address format, 133
forwarding
interface outbound PBR configuration, 363
interface PBR configuration, 362
interface PBR configuration (packet type-based), 365
IP routing inter-protocol FRR, 6
IP routing IPv4 RIB inter-protocol FRR, 6
IP routing IPv6 RIB inter-protocol FRR, 6
IP routing RIB NSR, 5
IPv4 RIB NSR configuration, 5
IPv6 IS-IS BFD configuration, 452, 461
IPv6 PBR configuration, 467, 468, 470, 471
IPv6 PBR interface configuration, 470
IPv6 PBR interface configuration (packet type-based), 473
IPv6 PBR local configuration, 470
IPv6 PBR local configuration (packet type-based), 471
IPv6 PBR policy configuration, 469
IPv6 RIB NSR configuration, 5
local PBR configuration, 362
local PBR configuration (packet type-based), 364
OSPF GR, 97
OSPF GR helper, 98
OSPF GR restarter, 97
OSPF NSR, 99
OSPF NSR configuration, 124
OSPFv3 BFD, 419
OSPFv3 NSR, 418
OSPFv3 NSR configuration, 440
PBR configuration, 358, 360, 362, 364
PBR policy configuration, 360
RIPng NSR, 387
RIPng NSR configuration, 395
fragment
IS-IS LSP fragment extension, 151
FRR
BFD enable, 41, 388
BGP configuration, 289
IP routing inter-protocol FRR, 6
IP routing IPv4 RIB inter-protocol FRR, 6
IP routing IPv6 RIB inter-protocol FRR, 6
IPv4 BGP FRR configuration, 330
IPv6 BGP FRR configuration, 353
IPv6 IS-IS FRR, 453
IPv6 IS-IS FRR automatic backup next hop (LFA calculation), 454
IPv6 IS-IS FRR BFD, 454
IPv6 IS-IS FRR configuration, 463
IPv6 IS-IS FRR configuration (routing policy), 454
IS-IS FRR, 161
IS-IS FRR backup next hop configuration (LFA calculation), 162
IS-IS FRR BFD enable (control packet mode), 163
IS-IS FRR BFD enable (echo packet mode), 163
IS-IS FRR configuration, 187
IS-IS FRR configuration (routing policy), 162
OSPF backup next hop (routing policy), 101
OSPF backup next hop calculation (LFA algorithm), 101
OSPF FRR BFD, 101
OSPF FRR configuration, 100, 129
OSPFv3 backup next hop (routing policy), 421
OSPFv3 backup next hop calculation (LFA algorithm), 420
OSPFv3 FRR BFD, 421
OSPFv3 FRR configuration, 419, 444
RIP configuration, 40, 61, 387
RIPng configuration, 397
RIPng FRR configuration, 388
static routing FRR configuration, 12, 20
G
garbage-collect timer (RIP), 32
Generalized TTL Security Mechanism. Use GTSM
generating
BGP route, 221
OSPFv3 LSA generation interval, 411
Graceful Restart (GR)
BGP configuration, 283
BGP NSR configuration, 284
GR helper, 283
GR restarter, 283
IPv4 BGP GR configuration, 325
IS-IS GR configuration, 159, 180
IS-IS GR helper, 159
IS-IS GR restarter, 159
IS-IS NSR, 160
IS-IS NSR configuration, 181
OSPF GR configuration, 97, 121
OSPF GR helper configuration, 98
OSPF GR restarter configuration, 97
OSPF NSR, 99
OSPF trigger, 98
OSPFv3 GR configuration, 417, 439
OSPFv3 GR helper configuration, 418
OSPFv3 GR restarter configuration, 417
OSPFv3 trigger, 418
RIP configuration, 37, 51
RIP GR helper configuration, 37
RIP GR restarter configuration, 37
RIP NSR enable, 38
RIPng configuration, 386, 394
group
BGP peer group, 211
BGP configuration, 267
OSPF configuration, 96
H
hello
IS-IS hello multiplier, 147
IS-IS hello packet send interval, 147
IS-IS interface hello packet send, 149
IS-IS PDU type, 138
OSPF hello packet, 64
OSPF hello packet timer, 84
OSPFv3 packet type, 400
HO-DSP (IS-IS area address), 134
holdtime (BGP), 258
hop
BGP NEXT_HOP attribute, 248
EBGP session establishment (multiple hop), 260, 260
OSPF BFD detection configuration (single-hop echo), 100
RIP BFD configuration (bidirectional control detection), 40
RIP BFD configuration (single-hop echo detection/neighbor), 39
RIP BFD configuration (single-hop echo detection/specific destination), 39
host
IS-IS system ID > host name mapping, 154
OSPF host route advertisement, 83
host route reception, 30
I
BGP confederation, 282
peer, 191
peer group configuration (IPv4 multicast address), 211
peer group configuration (IPv4 unicast address), 211
peer group configuration (IPv6 multicast address), 211
peer group configuration (IPv6 unicast address), 211
ICMP
OSPF area configuration (NSSA), 113
OSPF area configuration (stub), 111
OSPF basic configuration, 104
OSPF BFD configuration, 126
OSPF configuration, 64, 70, 104
OSPF DR election configuration, 115
OSPF FRR configuration, 129
OSPF GR configuration, 121
OSPF route redistribution configuration, 106
OSPF route summarization configuration, 108
OSPF virtual link configuration, 119
OSPFv3 FRR configuration, 444
OSPFv3 route summarization, 435
ID
BGP link state (LS) router ID, 296
IS-IS system ID, 134
IDP (IS-IS area address), 134
IETF
OSPF GR, 97
OSPF GR helper, 98
OSPF GR restarter, 97
ignoring
BGP AS_PATH attribute, 251
BGP first AS number of EBGP route updates, 255
BGP IGP metrics during optimal route selection, 255
BGP ORIGINATOR_ID attribute (IPv4), 281
BGP ORIGINATOR_ID attribute (IPv6), 281
OSPFv3 DD packet MTU check, 412
IGP
BGP IGP metrics ignore, 255
BGP IGP route redistribution, 223
BGP ORIGIN path attribute, 191
IPv4 BGP+IGP route redistribution, 304
IS-IS authentication configuration, 177
IS-IS basic configuration, 140
IS-IS basics configuration, 165
IS-IS configuration, 133, 139, 165
IS-IS DIS election configuration, 169
IS-IS route redistribution, 173
RIP BFD configuration (bidirectional control detection), 40
RIP BFD configuration (single-hop echo detection/neighbor), 39
RIP BFD configuration (single-hop echo detection/specific destination), 39
RIP configuration, 24, 25, 42
RIP neighbor specification, 35
INCOMPLETE
BGP ORIGIN path attribute, 191
injecting
BGP local network (IPv4), 221
BGP local network (IPv6), 221
instance
BGP multi-instance, 201
inter-area
OSPF route type, 68
interface
interface PBR configuration (packet type-based), 365
IPv6 PBR interface configuration, 470
IPv6 PBR interface configuration (packet type-based), 473
outbound PBR configuration, 363
PBR configuration, 362
Intermediate System-to-Intermediate System. Use IS-IS
internal
BGP. Use IBGP
OSPF router type, 67
INTERNET
BGP COMMUNITY path attribute, 191
interval
BGP keepalive interval, 258
BGP route update interval, 259
BGP soft reset, 268
IPv6 IS-IS SPF calculation interval, 451
IS-IS CSNP packet send interval, 148
IS-IS hello multiplier, 147
IS-IS hello packet send interval, 147
IS-IS SPF calculation interval, 151
OSPF exit overflow interval, 89
OSPF LSA arrival interval, 86
OSPF LSA generation interval, 86
OSPF LSU transmit rate, 91
OSPF SPF calculation interval, 85
OSPFv3 LSA generation interval, 411
OSPFv3 LSU transmit rate, 414
OSPFv3 SPF calculation interval, 411
RIP triggered update interval, 35
RIPng triggered update send interval, 386
intra-area
OSPF route type, 68
IP addressing
RIP configuration, 24, 25, 42
RIP update source IP address check, 34
IP routing
advertising OSPF link state information to BGP, 102
BGP 6PE optional capabilities, 293
BGP AS_PATH attribute, 250
BGP COMMUNITY configuration, 278
BGP confederation, 282
BGP configuration, 191, 203
BGP default local preference, 242
BGP default route advertisement (peer/peer group), 228
BGP display, 296
BGP dynamic peer, 209
BGP first AS number of EBGP route update ignore, 255
BGP FRR, 289
BGP GR, 283
BGP GTSM configuration, 267
BGP large scale network management, 197
BGP large-scale network, 278
BGP load balancing, 196, 265
BGP maintain, 296
BGP MED attribute, 244
BGP MPLS local label update delay, 275
BGP network optimization, 258
BGP NEXT_HOP attribute, 248
BGP NSR, 284
BGP optimal route advertisement, 227
BGP path selection, 239
BGP peer, 207
BGP peer (IPv4 unicast address), 207
BGP peer (IPv6 unicast address), 208
BGP peer group, 211
BGP peer keychain authentication, 264
BGP peer MD5 authentication, 263
BGP protocols and standards, 203
BGP received route preferred value, 239
BGP route dampening configuration, 238
BGP route distribution, 224
BGP route filtering policy, 231
BGP route flapping logging, 286
BGP route generation, 221
BGP route preference, 241
BGP route reception, 224
BGP route recursion, 196
BGP route reflection, 280
BGP route selection, 195, 196
BGP route summarization, 224
BGP route update delay, 237
BGP route update interval, 259
BGP session establishment disable, 266
BGP session state change logging, 285
BGP SNMP notification enable, 285
BGP soft reset, 268
BGP SoO attribute, 256
BGP suboptimal route flush to RIB, 276
BGP TCP connection source address, 220
configuration, 1
dynamic routing protocols, 2
EBGP peer protection (low memory exemption), 274
excluding interfaces in an OSPF area from the base topology, 83
extension attribute redistribution, 3
FIB route max lifetime, 4
interface outbound PBR configuration, 363
interface PBR configuration, 362
inter-protocol FRR configuration, 6
IPv4 ECMP enhanced mode enable, 7
IPv4 RIB inter-protocol FRR configuration, 6
IPv6 default route. See under IPv6 static routing
IPv6 IS-IS, 447, See also IPv6 IS-IS
IPv6 IS-IS display, 456
IPv6 IS-IS FRR, 453
IPv6 IS-IS FRR configuration, 463
IPv6 policy-based routing. See IPv6 PBR
IPv6 RIB inter-protocol FRR configuration, 6
IPv6 static routing. See IPv6 static routing
IPv6 static routing display, 370
IS-IS ATT bit, 153
IS-IS authentication (area), 158
IS-IS authentication (neighbor relationship), 158
IS-IS authentication (routing domain), 159
IS-IS authentication configuration, 177
IS-IS automatic cost calculation, 143
IS-IS basic configuration, 140
IS-IS basics configuration, 165
IS-IS BFD, 161
IS-IS BFD configuration, 184
IS-IS configuration, 133, 139, 165
IS-IS CSNP packet send interval, 148
IS-IS default route advertisement, 145
IS-IS DIS election configuration, 169
IS-IS display, 163
IS-IS ECMP routes max, 144
IS-IS FRR, 161
IS-IS FRR configuration, 187
IS-IS global cost, 143
IS-IS GR, 159
IS-IS GR configuration, 180
IS-IS hello multiplier, 147
IS-IS hello packet send interval, 147
IS-IS interface cost, 143
IS-IS interface DIS priority, 148
IS-IS interface hello packet send, 149
IS-IS interface packet send/receive, 148
IS-IS interface tag value, 153
IS-IS ISPF, 155
IS-IS link cost, 142
IS-IS LSDB overload bit, 152
IS-IS LSP flash flooding, 151
IS-IS LSP fragment extension, 151
IS-IS LSP length, 150
IS-IS LSP parameters, 149
IS-IS LSP timer, 149
IS-IS LSP-calculated route filtering, 146
IS-IS maintain, 163
IS-IS network management, 156
IS-IS network optimization, 147
IS-IS network security enhancement, 158
IS-IS network tuning, 147
IS-IS NSR, 160
IS-IS NSR configuration, 181
IS-IS PDU CLVs, 138
IS-IS PDU hello type, 138
IS-IS PDU LSP type, 138
IS-IS PDU SNP type, 138
IS-IS PDU types, 137
IS-IS PIC BFD, 157
IS-IS PICconfiguration, 157
IS-IS preference, 143
IS-IS prefix suppression, 155
IS-IS protocols and standards, 139
IS-IS redistributed route filtering, 146
IS-IS route control, 142
IS-IS route convergence priority, 152
IS-IS route filtering, 145
IS-IS route leaking, 136, 146
IS-IS route redistribution, 145, 173
IS-IS route summarization, 144
IS-IS routing domain, 135
IS-IS SPF calculation interval, 151
IS-IS system ID > host name mapping, 154
load sharing, 3
local PBR configuration, 362
MP-BGP, 200
MP-BGP protocols and standards, 203
OSPF area, 74
OSPF area configuration (NSSA), 75, 113
OSPF area configuration (stub), 74, 111
OSPF authentication, 88
OSPF basic configuration, 104
OSPF BDR, 69
OSPF BFD configuration, 126
OSPF BFD detection configuration (bidirectional control), 99
OSPF BFD detection configuration (single-hop echo), 100
OSPF configuration, 64, 70, 104
OSPF DD packet interface MTU, 89
OSPF display, 102
OSPF DR, 69
OSPF DR election configuration, 115
OSPF ECMP routes max, 81
OSPF exit overflow interval, 89
OSPF FRR, 100
OSPF FRR BFD, 101
OSPF FRR configuration, 129
OSPF GR, 97
OSPF GR configuration, 121
OSPF GR helper, 98
OSPF GR restarter, 97
OSPF GTSM configuration, 96
OSPF host route advertisement, 83
OSPF interface cost, 80
OSPF interface network type (broadcast), 76
OSPF interface network type (NBMA), 76
OSPF interface network type (P2MP), 77
OSPF interface network type (P2P), 78
OSPF interface packet send/receive disable, 87
OSPF ISPF, 92
OSPF log count, 95
OSPF LSA arrival interval, 86
OSPF LSA generation interval, 86
OSPF LSA transmission delay, 85
OSPF LSDB external LSAs max, 89
OSPF LSU transmit rate, 91
OSPF maintain, 102
OSPF network management, 91
OSPF network optimization, 84
OSPF network tuning, 84
OSPF network type, 76
OSPF NSR, 99
OSPF NSR configuration, 124
OSPF outbound LSA filtering (on interface), 95, 99
OSPF outbound LSA filtering (specified neighbor), 95
OSPF packet DSCP value, 90
OSPF PIC configuration, 94
OSPF preference, 81
OSPF prefix priority, 93
OSPF prefix suppression, 92
OSPF protocols and standards, 70
OSPF received route filtering, 79
OSPF RFC 1583 compatibility, 90
OSPF route control, 78
OSPF route redistribution, 82
OSPF route redistribution configuration, 106
OSPF route summarization, 78
OSPF route summarization configuration, 108
OSPF SPF calculation interval, 85
OSPF stub router, 87
OSPF summary network discard route, 81
OSPF timer set, 84
OSPF Type-3 LSA filtering, 80
OSPF virtual link, 75
OSPF virtual link configuration, 119
OSPFv3 area configuration (NSSA), 403, 427
OSPFv3 area configuration (stub), 403, 423
OSPFv3 area parameter, 403
OSPFv3 authentication, 416
OSPFv3 BFD, 419
OSPFv3 BFD configuration, 441
OSPFv3 configuration, 400, 401, 423
OSPFv3 DD packet ignore MTU check, 412
OSPFv3 display, 422
OSPFv3 DR election configuration, 429
OSPFv3 ECMP route max, 408
OSPFv3 enable, 402
OSPFv3 FRR, 419
OSPFv3 FRR BFD, 421
OSPFv3 FRR configuration, 444
OSPFv3 GR, 417
OSPFv3 GR configuration, 439
OSPFv3 GR helper, 418
OSPFv3 GR restarter, 417
OSPFv3 Inter-Area-Prefix LSA filtering, 407
OSPFv3 interface cost, 407
OSPFv3 interface DR priority, 412
OSPFv3 interface packet send/receive disable, 412
OSPFv3 LSA generation interval, 411
OSPFv3 LSA transmission delay, 411
OSPFv3 LSU transmit rate, 414
OSPFv3 maintain, 422
OSPFv3 NBMA neighbor, 405
OSPFv3 neighbor state change logging, 413
OSPFv3 network management traps, 413
OSPFv3 network optimization, 410
OSPFv3 network tuning, 410
OSPFv3 network type, 404
OSPFv3 network type (interface), 405
OSPFv3 NSR, 418
OSPFv3 NSR configuration, 440
OSPFv3 P2MP neighbor, 405
OSPFv3 preference, 408
OSPFv3 prefix suppression, 415
OSPFv3 protocols and standards, 401
OSPFv3 received route filtering, 407
OSPFv3 route control, 406
OSPFv3 route redistribution, 409, 432
OSPFv3 route summarization, 406, 435
OSPFv3 SPF calculation interval, 411
OSPFv3 stub router, 414
OSPFv3 timer, 410
OSPFv3 virtual link, 404
outgoing OSPF packet DSCP value, 89
outgoing RIP packet DSCP value, 37
PBR configuration, 360, 362, 364
PBR display, 363
PBR maintain, 363
PBR node action, 361
PBR node creation, 360
PBR node match criteria, 360
PBR policy, 358
PBR policy configuration, 360
PBR+Track collaboration, 359
policy apply clause, 481
policy AS_PATH list, 478
policy COMMUNITY list, 478
policy configuration, 476, 479, 483
policy configuration (IPv4 route redistribution), 483
policy configuration (IPv6 route redistribution), 486
policy continue clause, 482
policy creation, 479
policy display, 483
policy extended community list, 478
policy filter configuration, 477
policy filtering, 476
policy filters, 476
policy if-match clause, 479
policy IP prefix list, 477
policy maintain, 483
policy-based routing. Use PBR
RIB label max lifetime, 4
RIB nonstop routing (NSR) configuration, 5
RIB route max lifetime, 4
RIP additional routing metric configuration, 28
RIP basic configuration, 26, 42
RIP BFD configuration, 38
RIP BFD configuration (bidirectional control detection), 40
RIP BFD configuration (bidirectional detection/control packet mode), 58
RIP BFD configuration (single-hop echo detection), 53
RIP BFD configuration (single-hop echo detection/neighbor), 39
RIP BFD configuration (single-hop echo detection/specific destination), 39, 56
RIP configuration, 24, 25, 42
RIP default route advertisement, 30
RIP display, 41
RIP ECMP route max number, 33
RIP FRR configuration, 40, 61
RIP FRR configuration restrictions, 40
RIP GR configuration, 37, 51
RIP host route reception disable, 30
RIP interface additional metric configuration, 47
RIP interface advertisement control, 27
RIP interface reception control, 27
RIP maintain, 41
RIP neighbor specification, 35
RIP network management configuration, 36
RIP network optimization, 32
RIP network tuning, 32
RIP NSR configuration, 52
RIP NSR enable, 38
RIP operation, 24
RIP packet max length, 37
RIP packet send rate configuration, 36
RIP poison reverse configuration, 33
RIP preference configuration, 31
RIP received/redistributed route filtering, 30
RIP route control configuration, 28
RIP route entries, 24
RIP route redistribution, 45
RIP route redistribution configuration, 31
RIP routing loop prevention, 24
RIP split horizon configuration, 33
RIP summary route advertisement configuration, 48
RIP timer configuration, 32
RIP triggered update interval configuration, 35
RIP update source IP address check, 34
RIP version configuration, 27
RIP versions, 25
RIPng basic configuration, 380, 389
RIPng configuration, 379, 380, 389
RIPng default route advertisement, 382
RIPng display, 389
RIPng ECMP route max, 385
RIPng FRR configuration, 387, 397
RIPng GR configuration, 386, 394
RIPng maintain, 389
RIPng network optimization, 383
RIPng network tuning, 383
RIPng NSR, 387
RIPng NSR configuration, 395
RIPng packet, 379
RIPng packet send rate, 385
RIPng packet zero field check configuration, 384
RIPng poison reverse configuration, 384
RIPng preference, 382
RIPng protocols and standards, 380
RIPng received/redistributed route filtering, 382
RIPng route control, 381
RIPng route entry, 379
RIPng route redistribution, 383, 392
RIPng route summarization, 381
RIPng routing metric configuration, 381
RIPng split horizon configuration, 384
RIPng timer configuration, 383
RIPng triggered update send interval, 386
RIPv1 message zero field check, 34
RIPv2 message authentication configuration, 34
RIPv2 route summarization configuration, 29
route backup, 3
route preference, 2
route recursion, 3
route redistribution, 3
routing table, 1
routing table display, 7
routing table maintain, 7
setting maximum number of OSPFv3 logs, 416
setting maximum OSPF packet length, 92
static route display, 13
static routing basic configuration, 14
static routing BFD bidirectional control mode (direct next hop), 10
static routing BFD bidirectional control mode (indirect next hop), 10
static routing BFD configuration, 10
static routing BFD configuration (direct next hop), 15
static routing BFD configuration (indirect next hop), 18
static routing BFD echo mode (single-hop), 11
static routing configuration, 9, 9, 14
static routing default route configuration, 23
static routing FRR configuration, 12, 20
troubleshooting BGP, 357
troubleshooting BGP peer connection state, 357
troubleshooting OSPF configuration, 131
troubleshooting OSPF incorrect routing information, 132
troubleshooting OSPF no neighbor relationship established, 131
IPv4
BGP 6PE optional capabilities, 293
BGP dynamic peer configuration (IPv4 unicast address), 209
BGP peer configuration (IPv4 multicast address), 209
BGP SoO attribute, 256
BGP+IGP route redistribution, 304
EBGP peer group configuration (IPv4 multicast address), 213
EBGP peer group configuration (IPv4 unicast address), 213
EBGP peer protection (low memory exemption), 274
EBGP session establishment (multiple hop), 260
IBGP peer group configuration (IPv4 multicast address), 211
IBGP peer group configuration (IPv4 unicast address), 211
IP routing FIB route max lifetime, 4
IP routing RIB label max lifetime, 4
IP routing RIB route max lifetime, 4
IPv6 BGP 6PE configuration, 347
IS-IS authentication configuration, 177
IS-IS basic configuration, 140
IS-IS basics configuration, 165
IS-IS configuration, 133, 165
IS-IS DIS election configuration, 169
IS-IS route redistribution, 173
OSPF area configuration (NSSA), 113
OSPF area configuration (stub), 111
OSPF basic configuration, 104
OSPF BFD configuration, 126
OSPF configuration, 64, 70, 104
OSPF DR election configuration, 115
OSPF FRR configuration, 129
OSPF GR configuration, 121
OSPF route redistribution configuration, 106
OSPF route summarization configuration, 108
OSPF virtual link configuration, 119
OSPFv3 FRR configuration, 444
RIB NSR, 5
routing policy ACLs, 476
routing policy configuration, 476, 483
routing policy configuration (IPv4 route redistribution), 483
routing policy IP prefix list, 477
routing policy prefix list, 476
IPv4 BGP
4-byte AS number suppression, 262
6PE configuration, 292
AS number substitution, 252
basic configuration, 300
BFD configuration, 288, 326
COMMUNITY configuration, 278, 313
confederation configuration, 318
configuration, 203, 300
configuration views, 201
default local preference, 242
default route advertisement (peer/peer group), 228
display, 296
dynamic peer configuration, 337
dynamic peer configuration (IPv4 multicast address), 210
fake AS number advertisement, 251
FRR, 289, 289
FRR configuration, 330
GR configuration, 325
GTSM configuration, 267
IGP metrics ignore, 255
IGP route redistribution, 223
information clearance, 299
keepalive interval+hold time configuration, 258
load balancing, 265
load balancing configuration, 310
local AS number appearance, 250
local network injection, 221
LS configuration, 295
manual soft reset configuration, 272
MED default value, 244
multicast configuration, 334
NEXT_HOP attribute, 248
optimal route advertisement, 227
ORIGINATOR_ID attribute ignore, 281
path selection configuration, 322
peer keychain authentication, 264
peer MD5 authentication, 263
private AS number removal, 254
received route preferred value, 239
route dampening, 238
route distribution filtering policy, 231
route flapping logging, 286
route preference, 241
route reception filtering policy, 235
route reflector, 280
route reflector configuration, 316
route refresh enable, 269
route summarization, 307
route summarization (automatic), 224
route summarization (manual), 225
route update interval, 259
route update save, 270
routes received (peer/peer group), 230
session establishment disable, 266
session reset, 299
session state change logging, 285
TCP connection source address, 220
IPv6
EBGP peer group configuration (IPv6 multicast address), 213
EBGP peer group configuration (IPv6 unicast address), 213
EBGP peer protection (low memory exemption), 274
EBGP session establishment (multiple hop), 260
IBGP peer group configuration (IPv6 multicast address), 211
IBGP peer group configuration (IPv6 unicast address), 211
IP routing FIB route max lifetime, 4
IP routing RIB label max lifetime, 4
IP routing RIB route max lifetime, 4
IS-IS. See IPv6 IS-IS
OSPFv3 area configuration (NSSA), 403, 427
OSPFv3 area configuration (stub), 403, 423
OSPFv3 area parameter, 403
OSPFv3 BFD, 419
OSPFv3 BFD configuration, 441
OSPFv3 configuration, 400, 401, 423
OSPFv3 DD packet ignore MTU check, 412
OSPFv3 DR election configuration, 429
OSPFv3 ECMP route max, 408
OSPFv3 GR, 417
OSPFv3 GR configuration, 439
OSPFv3 GR helper, 418
OSPFv3 GR restarter, 417
OSPFv3 Inter-Area-Prefix LSA filtering, 407
OSPFv3 interface cost, 407
OSPFv3 interface DR priority, 412
OSPFv3 interface packet send/receive disable, 412
OSPFv3 LSA generation interval, 411
OSPFv3 LSA transmission delay, 411
OSPFv3 NBMA neighbor, 405
OSPFv3 neighbor state change logging, 413
OSPFv3 network optimization, 410
OSPFv3 network tuning, 410
OSPFv3 network type, 404
OSPFv3 network type (interface), 405
OSPFv3 P2MP neighbor, 405
OSPFv3 preference, 408
OSPFv3 received route filtering, 407
OSPFv3 route control, 406
OSPFv3 route redistribution, 409, 432
OSPFv3 route summarization, 406, 435
OSPFv3 SPF calculation interval, 411
OSPFv3 timer, 410
OSPFv3 virtual link, 404
policy-based routing. See IPv6 PBR
provider edge. See 6PE
RIB NSR, 5
RIP, 379, See also RIPng
RIPng GR configuration, 394
routing policy ACLs, 476
routing policy configuration, 476, 483
routing policy configuration (IPv6 route redistribution), 486
routing policy IP prefix list, 477
routing policy prefix list, 476
IPv6 BGP
4-byte AS number suppression, 262
6PE configuration, 292, 347
6PE optional capabilities, 293
AS number substitution, 252
basic configuration, 341
BFD configuration, 288, 350
COMMUNITY configuration, 278
configuration, 203, 341
configuration views, 201
default local preference, 242
default route advertisement (peer/peer group), 228
display, 296
dynamic peer configuration (IPv6 unicast address), 210
fake AS number advertisement, 251
FRR configuration, 353
GTSM configuration, 267
IGP route redistribution, 223
information clearance, 299
keepalive interval+hold time configuration, 258
load balancing, 265
local AS number appearance, 250
local network injection, 221
LS configuration, 295
manual soft reset configuration, 272
MED default value, 244
NEXT_HOP attribute, 248
optimal route advertisement, 227
ORIGINATOR_ID attribute ignore, 281
peer keychain authentication, 264
peer MD5 authentication, 263
private AS number removal, 254
received route preferred value, 239
route dampening, 238
route distribution filtering policy, 231
route flapping logging, 286
route preference, 241
route reception filtering policy, 235
route reflector, 280
route reflector configuration, 344
route refresh enable, 269
route summarization (manual), 225
route update interval, 259
route update save, 270
routes received (peer/peer group), 230
session establishment disable, 266
session reset, 299
session state change logging, 285
SoO attribute, 256
TCP connection source address, 220
basic configuration, 447, 456
BFD configuration, 452, 461
configuration, 447, 456
display, 456
FRR automatic backup next hop (LFA calculation), 454
FRR BFD enabling, 454
FRR configuration, 453, 463
FRR configuration (routing policy), 454
global cost configuration, 449
interface cost configuration, 449
interface tag value configuration, 451
ISPF enable, 452
link cost configuration, 449
LSDB overload bit, 451
MTR enable, 455
network optimization, 450
network tuning, 450
prefix suppression, 452
route control configuration, 448
route convergence priority assignment, 450
SPF calculation interval, 451
apply clause, 467
configuration, 467, 468, 470, 471
display, 471
if-match clause, 467
interface configuration, 470
interface configuration (packet type-based), 473
interface PBR, 467
local configuration, 470
local configuration (packet type-based), 471
local PBR, 467
maintain, 471
match mode/node clause relationship, 468
node action configuration, 469
node creation, 469
node match criteria, 469
policy, 467
policy configuration, 469
Track collaboration, 468
basic configuration (on switch), 370
BFD configuration, 368
BFD configuration (direct next hop)(on switch), 372
BFD configuration (indirect next hop)(on switch), 375
BFD control mode (direct next hop), 369
BFD control mode (indirect next hop), 369
BFD echo mode (single hop), 369
configuration, 368
configuration (on switch), 370
default route configuration, 378
display, 370
route configuration, 368
address format, 133
area, 135
area address, 134
ATT bit, 153
ATT bit default route calculation, 153
ATT bit Level-1 LSP, 153
authentication (area), 158
authentication (neighbor relationship), 158
authentication (routing domain), 159
authentication configuration, 177
basic configuration, 140, 165
BFD configuration, 161, 184
broadcast network type, 136
configuration, 133, 139, 165
CSNP packet send interval, 148
default route advertisement, 145
DIS election, 136, 169
display, 163
ECMP routes max, 144
enable, 141
enabling automatic cost calculation, 143
FRR backup next hop configuration (LFA calculation), 162
FRR BFD enable (control packet mode), 163
FRR BFD enable (echo packet mode), 163
FRR configuration, 161, 187
FRR configuration (routing policy), 162
global cost configuration, 143
GR configuration, 159, 180
hello multiplier, 147
hello packet send interval, 147
interface cost configuration, 143
interface DIS priority, 148
interface hello packet send enable, 149
interface P2P network type configuration, 141
interface packet send/receive disable, 148
interface tag value, 153
IPv6 IS-IS. See IPv6 IS-IS
IS+circuit level set, 141
ISPF enable, 155
Level-1 router, 135
Level-1-2 router, 135
Level-2 router, 135
link cost configuration, 142
LSDB overload bit, 152
LSP flash flooding, 151
LSP fragment extension, 151
LSP length specification, 150
LSP parameter configuration, 149
LSP timer configuration, 149
LSP-calculated route filtering, 146
maintain, 163
neighbor state change logging, 155
NET, 134
network management, 156
network optimization, 147
network security enhancement, 158
network tuning, 147
nonstop routing (NSR) configuration, 160, 181
NSAP address format, 133
N-SEL, 134
PDU CLVs, 138
PDU hello type, 138
PDU LSP type, 138
PDU SNP type, 138
PDU types, 137
PIC BFD enabling, 157
PIC configuration, 157
point-to-point network type, 136
preference specification, 143
prefix suppression enable, 155
protocols and standards, 139
pseudonode, 136
redistributed route filtering, 146
route control configuration, 142
route convergence priority, 152
route filtering, 145
route leaking, 136
route leaking configuration, 146
route redistribution, 145, 173
route summarization, 144
routing method, 134
SPF calculation interval, 151
system ID, 134
system ID > host name mapping, 154
terminology, 133
ISPF
IPv6 IS-IS enable, 452
OSPF ISPF, 92
K
keepalive
BGP keepalive interval, 258
BGP route update interval, 259
keychain
IPv4 BGP peer keychain authentication, 264
IPv6 BGP peer keychain authentication, 264
OSPFv3 authentication, 416
L
label
BGP MPLS local label update delay, 275
BGP per-prefix label allocation enable, 277
IP routing RIB label max lifetime, 4
leaking
IS-IS routes, 146
level
EBGP peer protection (level 2 threshold exemption), 274
Level-1
IS-IS ATT bit Level-1 LSP, 153
limiting
BGP routes received (peer/peer group)(IPv4), 230
BGP routes received (peer/peer group)(IPv6), 230
link
BGP BFD, 288
EBGP direct connection after link failure, 261
IPv6 IS-IS automatic link cost calculation, 449
IPv6 IS-IS link cost, 449
IS-IS automatic cost calculation, 143
IS-IS global cost, 143
IS-IS interface cost, 143
IS-IS link cost, 142
IS-IS NSR, 160
OSPF configuration, 64, 70
OSPF FRR, 100
OSPF virtual link, 66, 75
OSPF virtual link configuration, 119
OSPFv3 FRR, 419
OSPFv3 virtual link, 404
link state
advertising OSPF information to BGP, 102
list
routing policy AS_PATH list, 476, 478
routing policy COMMUNITY list, 476, 478
routing policy extended community list, 476, 478
routing policy IP prefix list, 477
routing policy prefix list, 476
load balancing, 196, See also ECMP
BGP, 196
BGP configuration, 265
IP routing RIB NSR, 5
IPv4 BGP load balancing configuration, 310
IPv4 ECMP enhanced mode, 7
OSPF ECMP routes max, 81
OSPFv3 ECMP route max, 408
RIPng ECMP route max, 385
load sharing
IP routing load sharing, 3
IS-IS ECMP routes max, 144
RIP ECMP route max number, 33
local
BGP default local preference, 242
BGP local AS number appearance, 250
BGP local network injection, 221
BGP LOCAL_PREF path attribute, 191
BGP MPLS local label update delay, 275
IPv6 PBR local configuration, 470
IPv6 PBR local configuration (packet type-based), 471
local PBR configuration (packet type-based), 364
PBR configuration, 362
logging
BGP route flapping logging, 286
BGP session state change logging, 285
IS-IS neighbor state change, 155
OSPF log count, 95
OSPFv3 neighbor state change logging, 413
loop
BGP FRR, 289
RIP routing loop prevention, 24
LS
BGP link state (LS) AS number, 296
BGP link state (LS) route reflection, 295
BGP link state (LS) router ID, 296
BGP LS configuration, 295
LSA
OSPF AS External LSA, 64
OSPF ASBR summary LSA, 64
OSPF exit overflow interval, 89
OSPF LSA arrival interval, 86
OSPF LSA generation interval, 86
OSPF LSA retransmission packet timer, 84
OSPF LSA transmission delay, 85
OSPF LSDB external LSAs max, 89
OSPF network LSA, 64
OSPF network summary LSA, 64
OSPF NSSA LSA, 64
OSPF opaque LSA, 64
OSPF outbound LSA filtering (specified neighbor), 95
OSPF router LSA, 64
OSPF Type-3 LSA filtering, 80
OSPFv3 AS external LSA, 400
OSPFv3 grace LSA, 400
OSPFv3 inter-area-prefix LSA, 400
OSPFv3 Inter-Area-Prefix LSA filtering, 407
OSPFv3 inter-area-router LSA, 400
OSPFv3 intra-area-prefix LSA, 400
OSPFv3 link LSA, 400
OSPFv3 LSA generation interval, 411
OSPFv3 LSA transmission delay, 411
OSPFv3 network LSA, 400
OSPFv3 NSSA LSA, 400
OSPFv3 router LSA, 400
LSAck
OSPF LSAck packet, 64
OSPFv3 packet type, 400
LSDB
IPv6 IS-IS LSDB overload bit, 451
IS-IS LSDB overload bit, 152
OSPF LSDB external LSAs max, 89
LSP
IS-IS ATT bit Level-1 LSP, 153
IS-IS LSP flash flooding, 151
IS-IS LSP fragment extension, 151
IS-IS LSP length, 150
IS-IS LSP parameters, 149
IS-IS LSP timers, 149
IS-IS PDU type, 138
IS-IS route summarization, 144
LSR
OSPF LSR packet, 64
OSPFv3 packet type, 400
LSU
OSPF LSU packet, 64
OSPF LSU transmit rate, 91
OSPFv3 LSU transmit rate, 414
OSPFv3 packet type, 400
M
maintaining
BGP, 296
IP routing table, 7
IPv6 PBR, 471
IS-IS, 163
OSPF, 102
OSPFv3, 422
PBR, 363
RIP, 41
RIPng, 389
routing policy, 483
managing
BGP large scale network management, 197
manual
BGP route summarization (IPv4), 225
BGP route summarization (IPv6), 225
mapping
IS-IS system ID > host name mapping, 154
IS-IS system ID > host name mapping (dynamic), 154
IS-IS system ID > host name mapping (static), 154
matching
IPv6 PBR if-match clause, 467
IPv6 PBR node match criteria, 469
PBR deny match mode, 358
PBR if-match clause, 358
PBR node match criteria, 360
PBR permit match mode, 358
routing policy if-match clause, 476, 479
MD5
BGP peer MD5 authentication, 263
MED
BGP attribute configuration, 244
BGP MED default value, 244
BGP MED route comparison (confederation peers), 247
BGP MED route comparison (diff ASs), 245
BGP MED route comparison (per-AS), 245
BGP path attribute, 191
memory
EBGP peer protection (low memory exemption), 274
message
BGP notification, 191
BGP open, 191
BGP route-refresh, 191
BGP update, 191
RIPv1 message zero field check enable, 34
RIPv2 message authentication configuration, 34
metric
RIP additional routing metric configuration, 28
RIP interface additional metric configuration, 47
RIPng routing metric configuration, 381
MIB
OSPF network management, 91
mode
IPv4 ECMP enhanced mode, 7
IPv6 static route BFD control (direct next hop), 369
IPv6 static route BFD control (indirect next hop), 369
IPv6 static route BFD echo (single hop), 369
PBR deny match, 358
PBR permit match, 358
static routing BFD bidirectional control mode (direct next hop), 10
static routing BFD bidirectional control mode (indirect next hop), 10
static routing BFD echo mode (single-hop), 11
MP_REACH_NLRI (MP-BGP), 200
MP_UNREACH_NLRI (MP-BGP), 200
address family, 200
BGP configuration, 191, 203
extended attributes, 200
IPv4 BGP basic configuration, 300
IPv4 BGP BFD configuration, 326
IPv4 BGP COMMUNITY configuration, 313
IPv4 BGP confederation, 318
IPv4 BGP configuration, 300
IPv4 BGP FRR configuration, 330
IPv4 BGP GR configuration, 325
IPv4 BGP load balancing configuration, 310
IPv4 BGP path selection, 322
IPv4 BGP route reflector configuration, 316
IPv4 BGP route summarization, 307
IPv4 BGP+IGP route redistribution, 304
IPv6 BGP basic configuration, 341
IPv6 BGP BFD configuration, 350
IPv6 BGP configuration, 341
IPv6 BGP FRR configuration, 353
IPv6 BGP route reflector configuration, 344
overview, 200
protocols and standards, 203
MPLS
BGP 6PE configuration, 292
BGP 6PE optional capabilities, 293
IPv6 BGP 6PE configuration, 347
routing policy extended community list, 476
MPU
OSPF NSR, 99
OSPFv3 NSR, 418
OSPFv3 NSR configuration, 440
MTR
IPv6 IS-IS MTR enable, 455
MTU
OSPF DD packet interface MTU, 89
OSPFv3 DD packet ignore MTU check, 412
multicast
BGP dynamic peer, 209
EBGP peer group configuration (IPv4 multicast address), 213
EBGP peer group configuration (IPv6 multicast address), 213
IBGP peer group configuration (IPv4 multicast address), 211
IBGP peer group configuration (IPv6 multicast address), 211
OSPF network type, 69
RIPng basic configuration, 380
RIPng configuration, 379, 380
multicast BGP
dynamic peer configuration (IPv4 multicast address), 210
IPv4 BGP dynamic peer configuration, 337
IPv4 configuration, 334
peer, 207
peer configuration (IPv4 multicast address), 209
Multiprotocol Extensions for BGP-4. See MP-BGP
N
naming
IS-IS system ID > host name mapping, 154
NBMA
OSPF interface network type, 76
OSPF network type, 69, 76
OSPFv3 NBMA neighbor, 405
OSPFv3 network type, 404
OSPFv3 network type (interface), 405
ND
OSPFv3 BFD configuration, 441
OSPFv3 configuration, 423
OSPFv3 GR configuration, 439
OSPFv3 neighbor state change logging, 413
OSPFv3 route control, 406
OSPFv3 route redistribution, 432
neighbor
BGP BFD, 288
IS-IS authentication (neighbor relationship), 158
IS-IS neighbor state change logging, 155
OSPF outbound LSAs (specified neighbor), 95
RIP neighbor specification, 35
neighbor discovery
OSPFv3 area configuration (NSSA), 427
OSPFv3 area configuration (stub), 423
OSPFv3 configuration, 400, 401
OSPFv3 DR election configuration, 429
OSPFv3 NBMA neighbor, 405
OSPFv3 P2MP neighbor, 405
network
advertising OSPF link state information to BGP, 102
BGP 4-byte AS number suppression, 262
BGP 6PE configuration, 292
BGP 6PE optional capabilities, 293
BGP AS number substitution, 252
BGP AS_PATH attribute, 250
BGP AS_PATH attribute ignore, 251
BGP basic configuration, 206
BGP BFD configuration, 288
BGP community configuration, 278
BGP confederation, 282
BGP default local preference, 242
BGP default route advertisement (peer/peer group), 228
BGP dynamic peer, 209
BGP fake AS number advertisement, 251
BGP FRR, 289
BGP GR, 283
BGP GTSM configuration, 267
BGP IGP metrics ignore, 255
BGP IGP route redistribution, 223
BGP keepalive interval+hold time configuration, 258
BGP large-scale network, 278
BGP link state (LS) AS number, 296
BGP link state (LS) route reflection, 295
BGP link state (LS) router ID, 296
BGP load balancing, 196, 265
BGP local network injection, 221
BGP LS configuration, 339
BGP MED attribute, 244
BGP MPLS local label update delay, 275
BGP NEXT_HOP attribute, 248
BGP NSR, 284
BGP optimal route advertisement, 227
BGP optimization, 258
BGP path selection, 239
BGP peer, 207
BGP peer group, 211
BGP peer keychain authentication, 264
BGP peer MD5 authentication, 263
BGP per-prefix label allocation enable, 277
BGP private AS number removal, 254
BGP route dampening, 238
BGP route distribution, 224
BGP route filtering policy, 231
BGP route flapping logging, 286
BGP route generation, 221
BGP route preference, 241
BGP route reception, 224
BGP route recursion, 196
BGP route reflection, 280
BGP route selection, 195, 196
BGP route summarization, 224
BGP route update delay, 237
BGP route update interval, 259
BGP routes received (peer/peer group), 230
BGP session establishment disable, 266
BGP session state change logging, 285
BGP SNMP notification enable, 285
BGP soft reset, 268
BGP SoO attribute, 256
BGP suboptimal route flush to RIB, 276
BGP TCP connection source address, 220
EBGP peer protection (low memory exemption), 274
EBGP session establishment (multiple hop), 260
entity title. Use NET
excluding interfaces in an OSPF area from the base topology, 83
interface PBR configuration (packet type-based), 365
IP routing dynamic routing protocols, 2
IP routing extension attribute redistribution, 3
IP routing FIB route max lifetime, 4
IP routing inter-protocol FRR, 6
IP routing IPv4 RIB inter-protocol FRR, 6
IP routing IPv6 RIB inter-protocol FRR, 6
IP routing load sharing, 3
IP routing RIB label max lifetime, 4
IP routing RIB NSR, 5
IP routing RIB route max lifetime, 4
IP routing route backup, 3
IP routing route preference, 2
IP routing route recursion, 3
IP routing route redistribution, 3
IPv4 BGP basic configuration, 300
IPv4 BGP BFD configuration, 326
IPv4 BGP COMMUNITY configuration, 313
IPv4 BGP confederation, 318
IPv4 BGP configuration, 300
IPv4 BGP dynamic peer configuration, 337
IPv4 BGP FRR configuration, 330
IPv4 BGP GR configuration, 325
IPv4 BGP load balancing configuration, 310
IPv4 BGP path selection, 322
IPv4 BGP received route preferred value, 239
IPv4 BGP route reflector configuration, 316
IPv4 BGP route summarization, 307
IPv4 BGP+IGP route redistribution, 304
IPv4 multicast BGP configuration, 334
IPv4 RIB NSR configuration, 5
IPv6 BGP 6PE configuration, 347
IPv6 BGP basic configuration, 341
IPv6 BGP BFD configuration, 350
IPv6 BGP FRR configuration, 353
IPv6 BGP received route preferred value, 239
IPv6 BGP route reflector configuration, 344
IPv6 IS-IS automatic link cost calculation, 449
IPv6 IS-IS basic configuration, 447, 456
IPv6 IS-IS BFD configuration, 452, 461
IPv6 IS-IS FRR, 453
IPv6 IS-IS FRR configuration, 463
IPv6 IS-IS global cost, 449
IPv6 IS-IS interface cost, 449
IPv6 IS-IS interface tag value, 451
IPv6 IS-IS ISPF enable, 452
IPv6 IS-IS link cost, 449
IPv6 IS-IS LSDB overload bit, 451
IPv6 IS-IS network optimization, 450
IPv6 IS-IS network tuning, 450
IPv6 IS-IS prefix suppression, 452
IPv6 IS-IS route control, 448
IPv6 IS-IS route convergence priority, 450
IPv6 IS-IS SPF calculation interval, 451
IPv6 PBR configuration, 470
IPv6 PBR interface configuration, 470
IPv6 PBR local configuration, 470
IPv6 PBR node action, 469
IPv6 PBR node creation, 469
IPv6 PBR node match criteria, 469
IPv6 PBR policy configuration, 469
IPv6 PBR+Track collaboration, 468
IPv6 RIB NSR configuration, 5
IPv6 static route BFD configuration, 368
IPv6 static route BFD control mode (direct next hop), 369
IPv6 static route BFD control mode (indirect next hop), 369
IPv6 static route BFD echo mode (single hop), 369
IPv6 static route configuration, 368
IPv6 static routing basic configuration (on switch), 370
IPv6 static routing BFD (direct next hop)(on switch), 372
IPv6 static routing BFD (indirect next hop)(on switch), 375
IS-IS area, 135
IS-IS ATT bit, 153, 153
IS-IS authentication (area), 158
IS-IS authentication (neighbor relationship), 158
IS-IS authentication (routing domain), 159
IS-IS authentication configuration, 177
IS-IS automatic cost calculation, 143
IS-IS basic configuration, 140
IS-IS basics configuration, 165
IS-IS BFD, 161
IS-IS BFD configuration, 184
IS-IS broadcast type, 136
IS-IS DIS election, 136
IS-IS DIS election configuration, 169
IS-IS enable, 141
IS-IS FRR, 161
IS-IS FRR configuration, 187
IS-IS global cost, 143
IS-IS GR, 159
IS-IS GR configuration, 180
IS-IS hello multiplier, 147
IS-IS hello packet send interval, 147
IS-IS interface cost, 143
IS-IS interface DIS priority, 148
IS-IS interface hello packet send, 149
IS-IS interface P2P network type, 141
IS-IS interface packet send/receive, 148
IS-IS interface tag value, 153
IS-IS IS+circuit level, 141
IS-IS ISPF, 155
IS-IS link cost, 142
IS-IS LSDB overload bit, 152
IS-IS LSP flash flooding, 151
IS-IS LSP fragment extension, 151
IS-IS LSP length, 150
IS-IS LSP parameters, 149
IS-IS LSP timer, 149
IS-IS neighbor state change logging, 155
IS-IS network management, 156
IS-IS network optimization, 147
IS-IS network tuning, 147
IS-IS NSR, 160
IS-IS NSR configuration, 181
IS-IS PIC BFD, 157
IS-IS PIC configuration, 157
IS-IS point-to-point type, 136
IS-IS preference, 143
IS-IS prefix suppression, 155
IS-IS pseudonode, 136
IS-IS route control, 142
IS-IS route convergence priority, 152
IS-IS route leaking, 136
IS-IS route redistribution, 173
IS-IS routing domain, 135
IS-IS security enhancement, 158
IS-IS SPF calculation interval, 151
IS-IS system ID > host name mapping, 154
local PBR configuration (packet type-based), 364
MP-BGP, 200
OSPF area, 74
OSPF area configuration (NSSA), 75, 113
OSPF area configuration (stub), 74, 111
OSPF basic configuration, 104
OSPF BFD configuration, 126
OSPF BFD detection configuration (bidirectional control), 99
OSPF BFD detection configuration (single-hop echo), 100
OSPF DD packet interface MTU, 89
OSPF DR election configuration, 115
OSPF ECMP routes max, 81
OSPF exit overflow interval, 89
OSPF FRR, 100
OSPF FRR configuration, 129
OSPF GR, 97
OSPF GR configuration, 121
OSPF GR helper, 98
OSPF GR restarter, 97
OSPF GTSM configuration, 96
OSPF host route advertisement, 83
OSPF interface cost, 80
OSPF interface network type (broadcast), 76
OSPF interface network type (NBMA), 76
OSPF interface network type (P2MP), 77
OSPF interface network type (P2P), 78
OSPF interface packet send/receive disable, 87
OSPF ISPF, 92
OSPF log count, 95
OSPF LSA arrival interval, 86
OSPF LSA generation interval, 86
OSPF LSA transmission delay, 85
OSPF LSDB external LSAs max, 89
OSPF LSU transmit rate, 91
OSPF network LSA, 64
OSPF network management, 91
OSPF network summary LSA, 64
OSPF network type, 76
OSPF NSR, 99
OSPF NSR configuration, 124
OSPF optimization, 84
OSPF outbound LSA filtering (on interface), 95, 99
OSPF outbound LSA filtering (specified neighbor), 95
OSPF packet DSCP value, 90
OSPF PIC configuration, 94
OSPF preference, 81
OSPF prefix priority, 93
OSPF prefix suppression, 92
OSPF received route filtering, 79
OSPF RFC 1583 compatibility, 90
OSPF route calculation, 68
OSPF route control, 78
OSPF route redistribution, 82
OSPF route redistribution configuration, 106
OSPF route summarization, 78
OSPF route summarization configuration, 108
OSPF route types, 68
OSPF SPF calculation interval, 85
OSPF stub router, 87
OSPF summary network discard route, 81
OSPF timer set, 84
OSPF tuning, 84
OSPF Type-3 LSA filtering, 80
OSPF virtual link, 75
OSPF virtual link configuration, 119
OSPFv3 area configuration (NSSA), 403, 427
OSPFv3 area configuration (stub), 403, 423
OSPFv3 area parameter, 403
OSPFv3 authentication, 416
OSPFv3 BFD, 419
OSPFv3 BFD configuration, 441
OSPFv3 DD packet ignore MTU check, 412
OSPFv3 DR election configuration, 429
OSPFv3 ECMP route max, 408
OSPFv3 enable, 402
OSPFv3 FRR, 419
OSPFv3 FRR configuration, 444
OSPFv3 GR, 417
OSPFv3 GR configuration, 439
OSPFv3 GR helper, 418
OSPFv3 GR restarter, 417
OSPFv3 Inter-Area-Prefix LSA filtering, 407
OSPFv3 interface cost, 407
OSPFv3 interface DR priority, 412
OSPFv3 interface packet send/receive disable, 412
OSPFv3 LSA generation interval, 411
OSPFv3 LSA transmission delay, 411
OSPFv3 LSU transmit rate, 414
OSPFv3 NBMA neighbor, 405
OSPFv3 neighbor state change logging, 413
OSPFv3 network management, 413
OSPFv3 network type, 404
OSPFv3 network type (interface), 405
OSPFv3 NSR, 418
OSPFv3 NSR configuration, 440
OSPFv3 P2MP neighbor, 405
OSPFv3 preference, 408
OSPFv3 prefix suppression, 415
OSPFv3 received route filtering, 407
OSPFv3 route control, 406
OSPFv3 route redistribution, 409, 432
OSPFv3 route summarization, 406, 435
OSPFv3 SPF calculation interval, 411
OSPFv3 stub router, 414
OSPFv3 timer, 410
OSPFv3 virtual link, 404
outgoing OSPF packet DSCP value, 89
outgoing RIP packet DSCP value, 37
PBR node action, 361
PBR node creation, 360
PBR node match criteria, 360
PBR policy, 358
PBR policy configuration, 360
PBR+Track collaboration, 359
RIP additional routing metric configuration, 28
RIP basic configuration, 26, 42
RIP BFD configuration, 38
RIP BFD configuration (bidirectional detection/control packet mode), 58
RIP BFD configuration (single-hop echo detection), 53
RIP BFD configuration (single-hop echo detection/specific destination), 56
RIP default route advertisement, 30
RIP ECMP route max number, 33
RIP enable, 26
RIP FRR configuration, 40, 61
RIP GR configuration, 37, 51
RIP host route reception disable, 30
RIP interface additional metric configuration, 47
RIP interface advertisement control, 27
RIP interface reception control, 27
RIP network management configuration, 36
RIP network optimization, 32
RIP network tuning, 32
RIP NSR configuration, 52
RIP NSR enable, 38
RIP operation, 24
RIP packet max length, 37
RIP packet send rate configuration, 36
RIP poison reverse configuration, 33
RIP preference configuration, 31
RIP received/redistributed route filtering, 30
RIP route control configuration, 28
RIP route entries, 24
RIP route redistribution, 45
RIP route redistribution configuration, 31
RIP routing loop prevention, 24
RIP split horizon configuration, 33
RIP summary route advertisement configuration, 48
RIP timer configuration, 32
RIP triggered update interval configuration, 35
RIP update source IP address check, 34
RIP version configuration, 27
RIP versions, 25
RIPng basic configuration, 380, 389
RIPng default route advertisement, 382
RIPng ECMP route max, 385
RIPng FRR configuration, 387, 397
RIPng GR configuration, 386, 394
RIPng network optimization, 383
RIPng network tuning, 383
RIPng NSR, 387
RIPng NSR configuration, 395
RIPng packet, 379
RIPng packet send rate, 385
RIPng packet zero field check, 384
RIPng poison reverse, 384
RIPng preference, 382
RIPng received/redistributed route filtering, 382
RIPng route control, 381
RIPng route entry, 379
RIPng route redistribution, 383, 392
RIPng route summarization, 381
RIPng routing metric configuration, 381
RIPng split horizon, 384
RIPng timer configuration, 383
RIPng triggered update send interval, 386
RIPv1 message zero field check, 34
RIPv2 message authentication configuration, 34
RIPv2 route summarization configuration, 29
routing policy apply clause, 481
routing policy AS_PATH list, 478
routing policy COMMUNITY list, 478
routing policy configuration, 479
routing policy configuration (IPv4 route redistribution), 483
routing policy configuration (IPv6 route redistribution), 486
routing policy continue clause, 482
routing policy creation, 479
routing policy extended community list, 478
routing policy filter configuration, 477
routing policy if-match clause, 479
routing policy IP prefix list, 477
setting maximum number of OSPFv3 logs, 416
setting maximum OSPF packet length, 92
static routing basic configuration, 14
static routing BFD bidirectional control mode (direct next hop), 10
static routing BFD bidirectional control mode (indirect next hop), 10
static routing BFD configuration, 10
static routing BFD configuration (direct next hop), 15
static routing BFD configuration (indirect next hop), 18
static routing BFD echo mode (single-hop), 11
static routing configuration, 9
static routing FRR configuration, 12, 20
tuning BGP, 258
network management
BGP configuration, 191, 203
BGP large scale networks, 197
IP routing configuration, 1
IPv6 BGP configuration, 341
IPv6 default route configuration, 378
IPv6 IS-IS configuration, 447, 456
IPv6 PBR configuration, 467, 468, 471
IPv6 PBR interface configuration (packet type-based), 473
IPv6 PBR local configuration (packet type-based), 471
IPv6 static routing configuration, 368
IPv6 static routing configuration (on switch), 370
IS-IS configuration, 133, 139, 165
OSPF configuration, 64, 70, 104
OSPFv3 configuration, 400, 401, 423
OSPFv3 network optimization, 410
OSPFv3 network tuning, 410
PBR configuration, 358, 360, 362, 364
RIP configuration, 24, 25, 42
RIPng configuration, 379, 380, 389
routing policy configuration, 476, 483
static routing configuration, 9, 14
static routing default route configuration, 23
NEXT_HOP
BGP attribute configuration, 248
BGP path attribute, 191
NO_ADVERTISE
BGP COMMUNITY path attribute, 191
NO_EXPORT
BGP COMMUNITY path attribute, 191
NO_EXPORT_SUBCONFED
BGP COMMUNITY path attribute, 191
node
IPv6 PBR node action, 469
IPv6 PBR node creation, 469
IPv6 PBR node match criteria, 469
IPv6 PBR policy, 467
IPv6 PBR+Track collaboration, 468
IS-IS pseudonode, 136
IS-IS route control, 142
PBR apply clause, 358
PBR creation, 360
PBR if-match clause, 358
PBR match criteria, 360
PBR node action, 361
PBR policy, 358
PBR-Track collaboration, 359
routing policy apply clause, 476, 481
routing policy continue clause, 476, 482
routing policy deny match, 476
routing policy if-match clause, 476, 479
routing policy permit match, 476
non-IETF
OSPF GR, 97
OSPF GR helper, 98
OSPF GR restarter, 97
nonstop routing (NSR)
BGP configuration, 284
IP routing RIB NSR, 5
RIP NSR enable, 38
RIPng configuration, 387
notifying
BGP notification message, 191
BGP SNMP notification enable, 285
OSPF network management, 91
NSAP
IS-IS address format, 133
NET, 134
N-SEL (IS-IS), 134
NSR
IPv4 RIB NSR configuration, 5
IPv6 RIB NSR configuration, 5
IS-IS NSR, 160
IS-IS NSR configuration, 181
OSPF configuration, 99
OSPF NSR configuration, 124
OSPFv3 NSR, 418
OSPFv3 NSR configuration, 440
RIP configuration, 52
RIPng NSR configuration, 395
NSSA
OSPF area configuration, 75, 113
OSPF NSSA area, 67
OSPF NSSA LSA, 64
OSPF totally NSSA area, 67
OSPFv3 area configuration, 427
OSPFv3 area configuration (NSSA), 403
number
BGP 4-byte AS number suppression, 262
BGP AS number substitution, 252
BGP fake AS number advertisement, 251
BGP first AS number of EBGP route update ignore, 255
BGP local AS number appearance, 250
BGP private AS number removal, 254
O
open
BGP message, 191
Open Shortest Path First. Use OSPF
Open Shortest Path First version 3. Use OSPFv3
optimal
BGP route advertisement, 227
IP routing FIB table optimal routes, 1
optimizing
BGP network, 258
IPv6 IS-IS networks, 450
IS-IS networks, 147
OSPF network, 84
OSPFv3 network, 410
RIP networks, 32
RIPng network, 383
ORIGIN
BGP path attribute, 191
advertising link state information to BGP, 102
area configuration, 74
area configuration (NSSA), 75, 113
area configuration (stub), 74, 111
areas, 65
authentication configuration, 88
backbone area, 66
basic configuration, 104
BDR, 69
BDR election, 70
BFD configuration, 126
BFD detection configuration (bidirectional control), 99
BFD detection configuration (single-hop echo), 100
BFD FRR configuration, 101
configuration, 64, 70, 104
DD packet interface MTU add, 89
display, 102
DR, 69
DR election, 70
DR election configuration, 115
ECMP routes max, 81
enable, 72
excluding interfaces in an OSPF area from the base topology, 83
exit overflow interval, 89
FRR backup next hop calculation (LFA algorithm), 101
FRR backup next hop specification (routing policy), 101
FRR configuration, 100
FRR configuration configuration, 129
GR configuration, 97, 121
GR helper, 98
GR restarter, 97
GR trigger, 98
GTSM configuration, 96
host route advertisement, 83
interface cost, 80
interface network type configuration (broadcast), 76
interface network type configuration (NBMA), 76
interface network type configuration (P2MP), 77
interface network type configuration (P2P), 78
interface packet send/receive disable, 87
IS-IS BFD, 161
IS-IS DIS election, 136
ISPF enable, 92
log count, 95
LSA arrival interval, 86
LSA generation interval, 86
LSA transmission delay, 85
LSA types, 64
LSDB external LSAs max, 89
LSU transmit rate configuration, 91
maintain, 102
network management configuration, 91
network optimization, 84
network tuning, 84
network type configuration, 76
network types, 69
nonstop routing (NSR) configuration, 99, 124
NSSA area, 67
outbound LSA filtering (on interface), 95, 99
outbound LSA filtering (specified neighbor), 95
outgoing packet DSCP value configuration, 89
packet DSCP value, 90
packet types, 64
PIC configuration, 94
PIC enable, 94
preference, 81
prefix priority configuration, 93
prefix suppression, 92
protocols and standards, 70
received route filtering configuration, 79
redistributed route default parameters, 83
redistributed route summarization (on ASBR), 79
RFC 1583 compatibility, 90
route calculation, 68
route control configuration, 78
route redistribution, 82
route redistribution configuration, 106
route summarization, 78
route summarization (on ABR), 78
route summarization configuration, 108
route types, 68
router types, 67
setting maximum OSPF packet length, 92
SPF calculation interval, 85
stub area, 66
stub router configuration, 87
summary network discard route, 81
timer set, 84
totally NSSA area, 67
totally stub area, 66
troubleshoot configuration, 131
troubleshoot incorrect routing information, 132
troubleshoot no neighbor relationship established, 131
Type-3 LSA filtering configuration, 80
virtual link configuration, 75, 119
virtual links, 66
area configuration (NSSA), 403, 427
area configuration (stub), 403, 423
area parameter configuration, 403
authentication, 416
authentication configuration (area), 416
authentication configuration (interface), 417
BFD configuration, 419, 441
BFD FRR configuration, 421
configuration, 400, 401, 423
DD packet ignore MTU check, 412
display, 422
DR election configuration, 429
ECMP route max, 408
enable, 402
FRR backup next hop calculation (LFA algorithm), 420
FRR backup next hop specification (routing policy), 421
FRR configuration, 419
FRR configuration configuration, 444
GR configuration, 417, 439
GR helper configuration, 418
GR restarter configuration, 417
GR trigger, 418
Inter-Area-Prefix LSA filtering, 407
interface cost configuration, 407
interface DR priority, 412
interface packet send/receive disable, 412
LSA generation interval, 411
LSA transmission delay, 411
LSA types, 400
LSU transmit rate, 414
maintain, 422
NBMA neighbor configuration, 405
neighbor state change logging, 413
network management configuration, 413
network optimization, 410
network tuning, 410
network type configuration, 404
network type configuration (interface), 405
nonstop routing (NSR) configuration, 418, 440
P2MP neighbor configuration, 405
packet types, 400
preference configuration, 408
prefix suppression, 415
protocols and standards, 401
received route filtering, 407
redistributed route tag, 410
route control configuration, 406
route redistribution, 409, 432
route redistribution (another routing protocol), 409
route redistribution (default route), 409
route summarization, 406, 435
route summarization (on ABR), 406
route summarization (on ASBR), 406
setting maximum number of OSPFv3 logs, 416
SPF calculation interval, 411
stub router configuration, 414
timer configuration, 410
virtual link configuration, 404
P
P2MP
OSPF interface network type, 77
OSPF network type, 69
OSPFv3 P2MP neighbor, 405
P2P
IS-IS network type, 141
OSPF interface network type, 78
OSPF network type, 69, 76
OSPFv3 network type, 404
OSPFv3 network type (interface), 405
packet
interface outbound PBR configuration, 363
interface PBR configuration, 362
interface PBR configuration (packet type-based), 365
IP routing configuration, 1
IP routing dynamic routing protocols, 2
IP routing extension attribute redistribution, 3
IP routing load sharing, 3
IP routing route backup, 3
IP routing route preference, 2
IP routing route recursion, 3
IP routing route redistribution, 3
IPv6 PBR configuration, 467, 468, 470, 471
IPv6 PBR interface configuration, 470
IPv6 PBR interface configuration (packet type-based), 473
IPv6 PBR local configuration, 470
IPv6 PBR local configuration (packet type-based), 471
IPv6 PBR policy, 467
IPv6 PBR policy configuration, 469
IS-IS CSNP packet send interval, 148
IS-IS hello multiplier, 147
IS-IS hello packet send interval, 147
IS-IS interface hello packet send, 149
IS-IS interface packet send/receive, 148
IS-IS PDU CLVs, 138
IS-IS PDU hello type, 138
IS-IS PDU LSP type, 138
IS-IS PDU SNP type, 138
IS-IS PDU types, 137
local PBR configuration, 362
local PBR configuration (packet type-based), 364
OSPF configuration, 64, 70
OSPF DD, 64
OSPF DD packet interface MTU, 89
OSPF exit overflow interval, 89
OSPF FRR, 100
OSPF GR, 97
OSPF GR helper, 98
OSPF GR restarter, 97
OSPF hello, 64
OSPF interface packet send/receive disable, 87
OSPF ISPF, 92
OSPF LSAck, 64
OSPF LSDB external LSAs max, 89
OSPF LSR, 64
OSPF LSU, 64
OSPF LSU transmit rate, 91
OSPF packet DSCP value, 90
OSPF RFC 1583 compatibility, 90
OSPF stub router, 87
OSPFv3 area configuration (NSSA), 427
OSPFv3 area configuration (stub), 423
OSPFv3 BFD configuration, 441
OSPFv3 configuration, 400, 401, 423
OSPFv3 DD, 400
OSPFv3 DD packet ignore MTU check, 412
OSPFv3 DR election configuration, 429
OSPFv3 FRR, 419
OSPFv3 GR configuration, 439
OSPFv3 hello, 400
OSPFv3 interface packet send/receive disable, 412
OSPFv3 LSAck, 400
OSPFv3 LSR, 400
OSPFv3 LSU, 400
OSPFv3 LSU transmit rate, 414
OSPFv3 route redistribution, 432
OSPFv3 stub router, 414
outgoing OSPF packet DSCP value, 89
outgoing RIP packet DSCP value, 37
PBR configuration, 358, 360, 362, 364
PBR policy configuration, 360
RIP BFD configuration (bidirectional control detection), 40
RIP BFD configuration (single-hop echo detection/neighbor), 39
RIP BFD configuration (single-hop echo detection/specific destination), 39
RIP network management configuration, 36
RIP packet max length, 37
RIP packet send rate configuration, 36
RIPng, 379
RIPng packet send rate, 385
RIPng packet zero field check, 384
RIPng triggered update send interval, 386
setting maximum OSPF packet length, 92
parameter
IPv6 IS-IS LSDB overload bit, 451
IPv6 IS-IS SPF calculation interval, 451
IS-IS LSDB overload bit, 152
IS-IS LSP parameters, 149
IS-IS route convergence priority, 152
IS-IS SPF calculation interval, 151
OSPF redistributed route default parameters, 83
OSPFv3 area parameter, 403
path
BGP MED attribute, 244
BGP MED route comparison (confederation peers), 247
BGP MED route comparison (diff ASs), 245
BGP MED route comparison (per-AS), 245
BGP NEXT_HOP attribute, 248
BGP path attributes, 191
BGP path selection, 239
IPv4 BGP COMMUNITY configuration, 313
IPv4 BGP path selection, 322
IPv4 multicast BGP configuration, 334
OSPF configuration, 64
configuration, 358, 360, 362, 364
display, 363
interface configuration, 362
interface configuration (packet type-based), 365
interface outbound configuration, 363
interface PBR, 358
local configuration, 362
local configuration (packet type-based), 364
local PBR, 358
maintain, 363
node action configuration, 361
node creation, 360
node match criteria, 360
policy, 358
policy configuration, 360
relationship between match mode/clauses, 359
Track collaboration, 359
PDU
IS-IS CLVs, 138
IS-IS hello type, 138
IS-IS LSP type, 138
IS-IS SNP type, 138
IS-IS types, 137
PE
BGP 6PE configuration, 292
BGP 6PE optional capabilities, 293
IPv6 BGP 6PE configuration, 347
peer
BGP, 191
BGP configuration, 207
BGP default route advertisement (peer/peer group), 228
BGP dynamic peer, 209
BGP large-scale network, 278
BGP MED route comparison (confederation peers), 247
BGP peer group, 211
BGP peer keychain authentication, 264
BGP peer MD5 authentication, 263
BGP session establishment disable, 266
EBGP, 191
EBGP peer protection (low memory exemption), 274
IBGP, 191
IPv4 BGP dynamic peer configuration, 337
IS-IS neighbor state change logging, 155
permitting
BGP local AS number appearance (IPv4), 250
BGP local AS number appearance (IPv6), 250
IS-IS PICconfiguration, 157
OSPF BFD, 94
OSPF configuration, 94
OSPF PIC enable, 94
point-to-point IS-IS network type, 136
poison reverse, 33, 33
RIPng configuration, 384
policy
BGP route distribution filtering policy, 231
BGP route filtering policy, 231
BGP route reception filtering policy, 235
interface outbound PBR configuration, 363
interface PBR configuration, 362
interface PBR configuration (packet type-based), 365
IPv6 IS-IS FRR configuration (routing policy), 454
IPv6 PBR, 467
IPv6 PBR apply clause, 467
IPv6 PBR configuration, 467, 468, 470, 471
IPv6 PBR if-match clause, 467
IPv6 PBR interface configuration, 470
IPv6 PBR interface configuration (packet type-based), 473
IPv6 PBR local configuration, 470
IPv6 PBR local configuration (packet type-based), 471
IPv6 PBR match mode/node clause relationship, 468
IPv6 PBR policy configuration, 469
IS-IS FRR configuration (routing policy), 162
local PBR configuration, 362
local PBR configuration (packet type-based), 364
OSPF FRR backup next hop (routing policy), 101
OSPFv3 FRR backup next hop (routing policy), 421
PBR, 358
PBR configuration, 358, 360, 360, 362, 364
PBR node action, 361
PBR node creation, 360
PBR node match criteria, 360
routing policy apply clause, 481
routing policy AS_PATH list, 478
routing policy COMMUNITY list, 478
routing policy configuration, 476, 479, 483
routing policy configuration (IPv4 route redistribution), 483
routing policy configuration (IPv6 route redistribution), 486
routing policy continue clause, 482
routing policy creation, 479
routing policy extended community list, 478
routing policy filter configuration, 477
routing policy filtering, 476
routing policy if-match clause, 479
routing policy IP prefix list, 477
policy-based routing. Use PBR
poll packet timer (OSPF), 84
preference
IP routing route preference, 2
OSPF route redistribution, 82
RIP configuration, 31
preferring
BGP default local preference, 242
BGP received route preferred value, 239
BGP route preference, 241
IS-IS preference specification, 143
OSPF protocol preference, 81
OSPFv3 preference, 408
RIPng preference, 382
prefix
IPv6 IS-IS prefix suppression, 452
IS-IS prefix suppression, 155
OSPF PIC configuration, 94
OSPF prefix priority, 93
OSPF prefix suppression, 92
OSPFv3 prefix suppression, 415
routing policy IP prefix list, 477
routing policy prefix list, 476
Prefix Independent Convergence. Use PIC
priority
IPv6 IS-IS route convergence priority, 450
IS-IS interface DIS priority, 148
IS-IS route convergence priority, 152
OSPF prefix priority configuration, 93
OSPF route level priority, 68
OSPFv3 interface DR priority, 412
procedure
adding OSPF DD packet interface MTU, 89
advertising BGP default route (peer/peer group)(IPv4), 228
advertising BGP default route (peer/peer group)(IPv6), 228
advertising BGP fake AS number (IPv4), 251
advertising BGP fake AS number (IPv6), 251
advertising BGP optimal route (IPv4 unicast), 227
advertising BGP optimal route (IPv6 unicast), 227
advertising IS-IS default route, 145
advertising OSPF host route, 83
advertising RIP default route, 30
advertising RIPng default route, 382
advertising RIPv2 summary route, 29
assigning IPv6 IS-IS route convergence priority, 450
clearing IPv4 BGP information, 299
clearing IPv6 BGP information, 299
configuring BGP, 203
configuring BGP 6PE, 292
configuring BGP 6PE basics, 292
configuring BGP 6PE optional capabilities, 293
configuring BGP AS number substitution (IPv4), 252
configuring BGP AS number substitution (IPv6), 252
configuring BGP AS_PATH attribute, 250
configuring BGP basics, 206
configuring BGP BFD (IPv4), 288
configuring BGP BFD (IPv6), 288
configuring BGP COMMUNITY (IPv4), 278
configuring BGP COMMUNITY (IPv6), 278
configuring BGP confederation, 282
configuring BGP confederation compatibility, 283
configuring BGP default local preference (IPv4), 242
configuring BGP default local preference (IPv6), 242
configuring BGP dynamic peer (IPv4 multicast address), 210
configuring BGP dynamic peer (IPv4 unicast address), 209
configuring BGP dynamic peer (IPv6 unicast address), 210
configuring BGP FRR (IPv4 unicast address), 289
configuring BGP FRR (IPv6 unicast address), 289
configuring BGP GR, 283
configuring BGP GTSM (IPv4), 267
configuring BGP GTSM (IPv6), 267
configuring BGP keepalive interval+hold time, 258
configuring BGP large-scale network, 278
configuring BGP link state (LS) route reflection, 295
configuring BGP LS, 295, 339
configuring BGP MED attribute, 244
configuring BGP MED default value (IPv4), 244
configuring BGP MED default value (IPv6), 244
configuring BGP MPLS local label update delay, 275
configuring BGP NEXT_HOP attribute (IPv4), 248
configuring BGP NEXT_HOP attribute (IPv6), 248
configuring BGP NSR, 284
configuring BGP peer (IPv4 multicast address), 209
configuring BGP peer (IPv4 unicast address), 207
configuring BGP peer (IPv6 unicast address), 208
configuring BGP route dampening (IPv4), 238
configuring BGP route dampening (IPv6), 238
configuring BGP route distribution filtering policy (IPv4), 231
configuring BGP route distribution filtering policy (IPv6), 231
configuring BGP route filtering policy, 231
configuring BGP route preference (IPv4), 241
configuring BGP route preference (IPv6), 241
configuring BGP route reception filtering policy (IPv4), 235
configuring BGP route reception filtering policy (IPv6), 235
configuring BGP route reflection, 280
configuring BGP route reflector (IPv4), 280
configuring BGP route reflector (IPv6), 280
configuring BGP route summarization (automatic)(IPv4), 224
configuring BGP route summarization (manual)(IPv4), 225
configuring BGP route summarization (manual)(IPv6), 225
configuring BGP route update delay, 237
configuring BGP route update interval (IPv4), 259
configuring BGP route update interval (IPv6), 259
configuring BGP soft reset, 268
configuring BGP soft reset manually (IPv4), 272
configuring BGP soft reset manually (IPv6), 272
configuring BGP SoO attribute (IPv4), 256
configuring BGP SoO attribute (IPv6), 256
configuring EBGP peer group (IPv4 multicast address), 213
configuring EBGP peer group (IPv4 unicast address), 213
configuring EBGP peer group (IPv6 multicast address), 213
configuring EBGP peer group (IPv6 unicast address), 213
configuring IBGP peer group (IPv4 multicast address), 211
configuring IBGP peer group (IPv4 unicast address), 211
configuring IBGP peer group (IPv6 multicast address), 211
configuring IBGP peer group (IPv6 unicast address), 211
configuring interface outbound PBR, 363
configuring interface PBR, 362
configuring interface PBR (packet type-based), 365
configuring inter-protocol FRR, 6
configuring IP routing RIB NSR, 5
configuring IP routing RIP GR, 51
configuring IP routing RIP NSR, 52
configuring IPv4 BGP basics, 300
configuring IPv4 BGP BFD, 326
configuring IPv4 BGP COMMUNITY, 313
configuring IPv4 BGP confederation, 318
configuring IPv4 BGP dynamic peer, 337
configuring IPv4 BGP FRR, 330
configuring IPv4 BGP GR, 325
configuring IPv4 BGP load balancing, 310
configuring IPv4 BGP path selection, 322
configuring IPv4 BGP route reflector, 316
configuring IPv4 BGP route summarization, 307
configuring IPv4 BGP+IGP route redistribution, 304
configuring IPv4 multicast BGP, 334
configuring IPv4 RIB inter-protocol FRR, 6
configuring IPv4 RIB NSR, 5
configuring IPv6 BGP 6PE, 347
configuring IPv6 BGP basics, 341
configuring IPv6 BGP BFD, 350
configuring IPv6 BGP FRR, 353
configuring IPv6 BGP route reflector, 344
configuring IPv6 IS-IS basics, 447, 456
configuring IPv6 IS-IS BFD, 452, 461
configuring IPv6 IS-IS FRR, 453, 463
configuring IPv6 IS-IS FRR (routing policy), 454
configuring IPv6 IS-IS FRR automatic backup next hop (LFA calculation), 454
configuring IPv6 IS-IS global cost, 449
configuring IPv6 IS-IS interface cost, 449
configuring IPv6 IS-IS interface tag value, 451
configuring IPv6 IS-IS link cost, 449
configuring IPv6 IS-IS route control, 448
configuring IPv6 PBR, 468, 470
configuring IPv6 PBR interface, 470
configuring IPv6 PBR interface (packet type-based), 473
configuring IPv6 PBR local, 470
configuring IPv6 PBR local (packet type-based), 471
configuring IPv6 PBR node action, 469
configuring IPv6 PBR policy, 469
configuring IPv6 RIB inter-protocol FRR, 6
configuring IPv6 RIB NSR, 5
configuring IPv6 static route, 368
configuring IPv6 static route BFD, 368
configuring IPv6 static route BFD control mode (direct next hop), 369
configuring IPv6 static route BFD control mode (indirect next hop), 369
configuring IPv6 static route BFD echo mode (single hop), 369
configuring IPv6 static routing basics (on switch), 370
configuring IPv6 static routing BFD (direct next hop)(on switch), 372
configuring IPv6 static routing BFD (indirect next hop)(on switch), 375
configuring IS-IS, 139
configuring IS-IS ATT bit, 153
configuring IS-IS ATT bit default route calculation, 153
configuring IS-IS authentication, 177
configuring IS-IS authentication (area), 158
configuring IS-IS authentication (neighbor relationship), 158
configuring IS-IS authentication (routing domain), 159
configuring IS-IS basics, 140, 165
configuring IS-IS BFD, 161, 184
configuring IS-IS DIS election, 169
configuring IS-IS ECMP routes max, 144
configuring IS-IS FRR, 161, 187
configuring IS-IS FRR (routing policy), 162
configuring IS-IS FRR backup next hop (LFA calculation), 162
configuring IS-IS global cost, 143
configuring IS-IS GR, 159, 180
configuring IS-IS interface cost, 143
configuring IS-IS interface DIS priority, 148
configuring IS-IS interface P2P network type, 141
configuring IS-IS interface tag value, 153
configuring IS-IS link cost, 142
configuring IS-IS LSP parameters, 149
configuring IS-IS LSP timer, 149
configuring IS-IS LSP-calculated route filtering, 146
configuring IS-IS network management, 156
configuring IS-IS NSR, 160, 181
configuring IS-IS PIC, 157
configuring IS-IS redistributed route filtering, 146
configuring IS-IS route control, 142
configuring IS-IS route convergence priority, 152
configuring IS-IS route filtering, 145
configuring IS-IS route leaking, 146
configuring IS-IS route redistribution, 145, 173
configuring IS-IS route summarization, 144
configuring IS-IS system ID > host name mapping, 154
configuring IS-IS system ID > host name mapping (dynamic), 154
configuring IS-IS system ID > host name mapping (static), 154
configuring local PBR, 362
configuring local PBR (packet type-based), 364
configuring OSPF, 70
configuring OSPF area, 74
configuring OSPF area (NSSA), 75, 113
configuring OSPF area (stub), 74, 111
configuring OSPF authentication (area), 88
configuring OSPF authentication (interface), 88
configuring OSPF basics, 104
configuring OSPF BFD, 126
configuring OSPF BFD detection (bidirectional control), 99
configuring OSPF BFD detection (single-hop echo), 100
configuring OSPF DR election, 115
configuring OSPF FRR, 100, 129
configuring OSPF FRR backup next hop (routing policy), 101
configuring OSPF FRR backup next hop calculation (LFA algorithm), 101
configuring OSPF FRR BFD, 101
configuring OSPF GR, 97, 121
configuring OSPF GR helper (IETF), 98
configuring OSPF GR helper (non-IETF), 98
configuring OSPF GR restarter, 97
configuring OSPF GR restarter (IETF), 97
configuring OSPF GR restarter (non-IETF), 97
configuring OSPF GTSM, 96
configuring OSPF interface cost, 80
configuring OSPF interface network type (broadcast), 76
configuring OSPF interface network type (NBMA), 76
configuring OSPF interface network type (P2MP), 77
configuring OSPF interface network type (P2P), 78
configuring OSPF network management, 91
configuring OSPF network type, 76
configuring OSPF NSR, 99, 124
configuring OSPF PIC, 94
configuring OSPF PIC BFD, 94
configuring OSPF prefix priority, 93
configuring OSPF prefix suppression (interface), 93
configuring OSPF prefix suppression (OSPF process), 93
configuring OSPF received route filtering, 79
configuring OSPF redistributed route default parameters, 83
configuring OSPF redistributed route summarization (on ASBR), 79
configuring OSPF route control, 78
configuring OSPF route redistribution, 106
configuring OSPF route summarization, 108
configuring OSPF route summarization (on ABR), 78
configuring OSPF stub router, 87
configuring OSPF summary network discard route, 81
configuring OSPF Type-3 LSA filtering, 80
configuring OSPF virtual link, 75, 119
configuring OSPFv3, 401
configuring OSPFv3 area (NSSA), 403, 427
configuring OSPFv3 area (stub), 403, 423
configuring OSPFv3 area parameter, 403
configuring OSPFv3 authentication, 416
configuring OSPFv3 authentication (area), 416
configuring OSPFv3 authentication (interface), 417
configuring OSPFv3 BFD, 419
configuring OSPFv3 BFD configuration, 441
configuring OSPFv3 DR election, 429
configuring OSPFv3 FRR, 419, 444
configuring OSPFv3 FRR backup next hop (routing policy), 421
configuring OSPFv3 FRR backup next hop calculation (LFA algorithm), 420
configuring OSPFv3 FRR BFD, 421
configuring OSPFv3 GR, 417, 439
configuring OSPFv3 GR helper, 418
configuring OSPFv3 GR restarter, 417
configuring OSPFv3 Inter-Area-Prefix LSA filtering, 407
configuring OSPFv3 interface cost, 407
configuring OSPFv3 interface DR priority, 412
configuring OSPFv3 LSU transmit rate, 414
configuring OSPFv3 NBMA neighbor, 405
configuring OSPFv3 network management, 413
configuring OSPFv3 network type, 404
configuring OSPFv3 network type (interface), 405
configuring OSPFv3 NSR, 418, 440
configuring OSPFv3 P2MP neighbor, 405
configuring OSPFv3 preference, 408
configuring OSPFv3 prefix suppression (interface), 416
configuring OSPFv3 prefix suppression (OSPFv3 process), 415
configuring OSPFv3 received route filtering, 407
configuring OSPFv3 redistributed route tag, 410
configuring OSPFv3 route control, 406
configuring OSPFv3 route redistribution, 432
configuring OSPFv3 route redistribution (another routing protocol), 409
configuring OSPFv3 route redistribution (default route), 409
configuring OSPFv3 route summarization, 435
configuring OSPFv3 route summarization (on ABR), 406
configuring OSPFv3 route summarization (on ASBR), 406
configuring OSPFv3 stub router, 414
configuring OSPFv3 virtual link, 404
configuring PBR, 360, 362
configuring PBR node action, 361
configuring PBR policy, 360
configuring RIP, 25
configuring RIP additional routing metric, 28
configuring RIP basics, 26, 42
configuring RIP BFD, 38
configuring RIP BFD (bidirectional control detection), 40
configuring RIP BFD (bidirectional detection/control packet mode), 58
configuring RIP BFD (single-hop echo detection), 53
configuring RIP BFD (single-hop echo detection/neighbor), 39
configuring RIP BFD (single-hop echo detection/specific destination), 39, 56
configuring RIP FRR, 40, 61
configuring RIP GR, 37
configuring RIP interface additional metric, 47
configuring RIP network management, 36
configuring RIP packet send rate, 36
configuring RIP received/redistributed route filtering, 30
configuring RIP route control, 28
configuring RIP route redistribution, 31, 45
configuring RIP split horizon, 33
configuring RIP summary route advertisement, 48
configuring RIP timers, 32
configuring RIP version, 27
configuring RIPng, 380
configuring RIPng basics, 380, 389
configuring RIPng FRR, 387, 388, 397
configuring RIPng GR, 386, 394
configuring RIPng NSR, 387, 395
configuring RIPng packet send rate, 385
configuring RIPng packet zero field check, 384
configuring RIPng poison reverse, 384
configuring RIPng received/redistributed route filtering, 382
configuring RIPng route control, 381
configuring RIPng route redistribution, 383, 392
configuring RIPng route summarization, 381
configuring RIPng routing metric, 381
configuring RIPng split horizon, 384
configuring RIPv2 message authentication, 34
configuring RIPv2 route summarization, 29
configuring routing policy, 479
configuring routing policy (IPv4 route redistribution), 483
configuring routing policy (IPv6 route redistribution), 486
configuring routing policy apply clause, 481
configuring routing policy AS_PATH list, 478
configuring routing policy COMMUNITY list, 478
configuring routing policy continue clause, 482
configuring routing policy extended community list, 478
configuring routing policy filter, 477
configuring routing policy if-match clause, 479
configuring routing policy IPv4 prefix list, 477
configuring routing policy IPv6 prefix list, 477
configuring static route, 9
configuring static route BFD, 10
configuring static route FRR (auto select backup next hop), 13
configuring static routing basics, 14
configuring static routing BFD (direct next hop), 15
configuring static routing BFD (indirect next hop), 18
configuring static routing BFD bidirectional control mode (direct next hop), 10
configuring static routing BFD bidirectional control mode (indirect next hop), 10
configuring static routing BFD echo mode (single-hop), 11
configuring static routing FRR, 12, 20
configuring static routing FRR (backup next hop), 12
controlling BGP path selection, 239
controlling BGP route distribution, 224
controlling BGP route reception, 224
controlling IPv6 IS-IS SPF calculation interval, 451
controlling IS-IS SPF calculation interval, 151
controlling RIP interface advertisement, 27
controlling RIP interface reception, 27
creating IPv6 PBR node, 469
creating PBR node, 360
creating routing policy, 479
disabling BGP optimal route selection for labeled routes, 277
disabling BGP session establishment (IPv4), 266
disabling BGP session establishment (IPv6), 266
disabling IS-IS interface packet send/receive, 148
disabling OSPF interface packet send/receive, 87
disabling OSPFv3 interface packet send/receive, 412
disabling RIP host route reception, 30
displaying BGP, 296
displaying IP routing table, 7
displaying IPv4 BGP, 296
displaying IPv6 BGP, 296
displaying IPv6 IS-IS, 456
displaying IPv6 PBR, 471
displaying IPv6 static routing, 370
displaying IS-IS, 163
displaying OSPF, 102
displaying OSPFv3, 422
displaying PBR, 363
displaying RIP, 41
displaying RIPng, 389
displaying routing policy, 483
displaying static routing, 13
enabling BGP, 206
enabling BGP 4-byte AS number suppression (IPv4), 262
enabling BGP 4-byte AS number suppression (IPv6), 262
enabling BGP load balancing (IPv4), 265
enabling BGP load balancing (IPv6), 265
enabling BGP MED route comparison (confederation peers), 247
enabling BGP MED route comparison (diff ASs), 245
enabling BGP MED route comparison (per-AS), 245
enabling BGP peer keychain authentication (IPv4), 264
enabling BGP peer keychain authentication (IPv6), 264
enabling BGP peer MD5 authentication (IPv4), 263
enabling BGP peer MD5 authentication (IPv6), 263
enabling BGP per-prefix label allocation, 277
enabling BGP route flapping logging (IPv4), 286
enabling BGP route flapping logging (IPv6), 286
enabling BGP route-refresh (IPv4), 269
enabling BGP route-refresh (IPv6), 269
enabling BGP session state change logging (IPv4), 285
enabling BGP session state change logging (IPv6), 285
enabling BGP SNMP notification, 285
enabling EBGP direct connections upon link failure, 261
enabling EBGP session establishment (multiple hop)(IPv4), 260
enabling EBGP session establishment (multiple hop)(IPv6), 260
enabling IPv4 ECMP enhanced mode, 7
enabling IPv6 BGP MED AS route comparison (confederation peers), 247
enabling IPv6 IS-IS automatic link cost calculation, 449
enabling IPv6 IS-IS FRR BFD, 454
enabling IPv6 IS-IS ISPF, 452
enabling IPv6 IS-IS MTR, 455
enabling IPv6 IS-IS prefix suppression, 452
enabling IS-IS, 141
enabling IS-IS automatic cost calculation, 143
enabling IS-IS FRR BFD (control packet mode), 163
enabling IS-IS FRR BFD (echo packet mode), 163
enabling IS-IS interface hello packet send, 149
enabling IS-IS ISPF, 155
enabling IS-IS LSP flash flooding, 151
enabling IS-IS LSP fragment extension, 151
enabling IS-IS neighbor state change logging, 155
enabling IS-IS PIC, 157
enabling IS-IS PIC BFD, 157
enabling IS-IS prefix suppression, 155
enabling OSPF, 72
enabling OSPF (on interface), 74
enabling OSPF (on network), 73
enabling OSPF ISPF, 92
enabling OSPF PIC, 94
enabling OSPF RFC 1583 compatibility, 90
enabling OSPFv3, 402
enabling OSPFv3 neighbor state change logging, 413
enabling RIP (on interface), 27
enabling RIP (on network), 26
enabling RIP FRR BFD, 41
enabling RIP NSR, 38
enabling RIP poison reverse, 33, 33
enabling RIP split horizon, 33
enabling RIP update source IP address check, 34
enabling RIPng FRR BFD, 388
enabling RIPv1 message zero field check, 34
enabling RIPv2 automatic route summarization, 29
enabling static routing FRR BFD echo packet mode, 13
enabling the device to advertise OSPF link state information to BGP, 102
enhancing IS-IS network security, 158
excluding interfaces in an OSPF area from the base topology, 83
filtering OSPF outbound LSA (on interface), 95, 99
filtering OSPF outbound LSAs (specified neighbor), 95
flushing BGP suboptimal route to RIB, 276
generating BGP route, 221
ignoring BGP AS_PATH attribute, 251
ignoring BGP first AS number of EBGP route updates, 255
ignoring BGP IGP metrics during optimal route selection, 255
ignoring BGP ORIGINATOR_ID attribute (IPv4), 281
ignoring BGP ORIGINATOR_ID attribute (IPv6), 281
ignoring OSPFv3 DD packet MTU check, 412
injecting BGP local network (IPv4), 221
injecting BGP local network (IPv6), 221
limiting BGP routes received (peer/peer group)(IPv4), 230
limiting BGP routes received (peer/peer group)(IPv6), 230
maintaining BGP, 296
maintaining IP routing table, 7
maintaining IPv6 PBR, 471
maintaining IS-IS, 163
maintaining OSPF, 102
maintaining OSPFv3, 422
maintaining PBR, 363
maintaining RIP, 41
maintaining RIPng, 389
maintaining routing policy, 483
optimizing BGP network, 258
optimizing IPv6 IS-IS networks, 450
optimizing IS-IS networks, 147
optimizing OSPF network, 84
optimizing OSPFv3 network, 410
optimizing RIP networks, 32
optimizing RIPng network, 383
permitting BGP local AS number appearance (IPv4), 250
permitting BGP local AS number appearance (IPv6), 250
protecting EBGP peer (low memory exemption)(IPv4), 274
protecting EBGP peer (low memory exemption)(IPv6), 274
redistributing BGP IGP route, 223
redistributing OSPF route (another routing protocol), 82
redistributing OSPF route (default route ), 82
removing BGP private AS number from EBGP peer/peer group update (IPv4), 254
removing BGP private AS number from EBGP peer/peer group update (IPv6), 254
resetting IPv4 BGP sessions, 299
resetting IPv6 BGP sessions, 299
saving BGP route update (IPv4), 270
saving BGP route update (IPv6), 270
setting BGP outgoing packet DSCP value, 276
setting BGP received route preferred value (IPv4), 239
setting BGP received route preferred value (IPv6), 239
setting IP routing FIB route max lifetime, 4
setting IP routing RIB label max lifetime, 4
setting IP routing RIB route max lifetime, 4
setting IPv6 IS-IS LSDB overload bit, 451
setting IPv6 PBR node match criteria, 469
setting IS-IS ATT bit Level-1 LSP, 153
setting IS-IS IS+circuit level, 141
setting IS-IS LSDB overload bit, 152
setting maximum number of OSPFv3 logs, 416
setting maximum OSPF packet length, 92
setting OSPF ECMP routes max, 81
setting OSPF exit overflow interval, 89
setting OSPF log count, 95
setting OSPF LSA arrival interval, 86
setting OSPF LSA generation interval, 86
setting OSPF LSA transmission delay, 85
setting OSPF LSDB external LSAs max, 89
setting OSPF LSU transmit rate, 91
setting OSPF packet DSCP value, 90
setting OSPF preference, 81
setting OSPF timer, 84
setting OSPFv3 ECMP route max, 408
setting OSPFv3 LSA generation interval, 411
setting OSPFv3 LSA transmission delay, 411
setting OSPFv3 SPF calculation interval, 411
setting OSPFv3 timer, 410
setting outgoing OSPF packet DSCP value, 89
setting outgoing RIP packet DSCP value, 37
setting PBR node match criteria, 360
setting RIP ECMP route max number, 33
setting RIP packet max length, 37
setting RIP preference, 31
setting RIP triggered update interval, 35
setting RIPng ECMP route max, 385
setting RIPng preference, 382
setting RIPng timer, 383
setting RIPng triggered update send interval, 386
specifying BGP link state (LS) AS number, 296
specifying BGP link state (LS) router ID, 296
specifying BGP TCP connection source address (IPv4), 220
specifying BGP TCP connection source address (IPv6), 220
specifying IS-IS CSNP packet send interval, 148
specifying IS-IS hello multiplier, 147
specifying IS-IS hello packet send interval, 147
specifying IS-IS LSP length, 150
specifying IS-IS preference, 143
specifying OSPF SPF calculation interval, 85
specifying RIP neighbor, 35
triggering OSPF GR, 98
triggering OSPFv3 GR, 418
troubleshooting BGP peer connection state, 357
troubleshooting OSPF incorrect routing information, 132
troubleshooting OSPF no neighbor relationship established, 131
tuning BGP network, 258
tuning IP routing OSPF network, 84
tuning IP routing RIP networks, 32
tuning IPv6 IS-IS network, 450
tuning IS-IS network, 147
tuning OSPFv3 network, 410
tuning RIPng network, 383
protecting
EBGP peer (low memory exemption)(IPv4), 274
EBGP peer (low memory exemption)(IPv6), 274
protocols and standards
BGP, 203
IP routing dynamic routing protocols, 2
IS-IS, 139
MP-BGP, 203
OSPF, 70
OSPF preference, 81
OSPF RFC 1583 compatibility, 90
OSPFv3, 401
RIP, 25
RIPng, 380
triggered RIP (TRIP), 25
R
rate
OSPFv3 LSU transmit rate, 414
receiving
BGP routes received (peer/peer group), 230
IS-IS interface packet send/receive, 148
OSPF interface packet send/receive disable, 87
OSPF received route filtering, 79
OSPFv3 interface packet send/receive disable, 412
RIPng received/redistributed route filtering, 382
recursion
BGP load balancing through route recursion, 196
BGP route recursion, 196, 196
IP routing route recursion, 3
redistributing
BGP IGP route, 223
BGP route generation, 221
IP routing extension attribute redistribution, 3
IP routing route redistribution, 3
IPv4 BGP+IGP route redistribution, 304
IS-IS redistributed route filtering, 146
IS-IS route redistribution, 145, 173
OSPF redistributed route default parameters, 83
OSPF route, 82
OSPF route (another routing protocol), 82
OSPF route (default route), 82
OSPF route redistribution configuration, 106
OSPFv3 redistributed route tag, 410
OSPFv3 route redistribution, 409, 432
OSPFv3 route redistribution (another routing protocol), 409
OSPFv3 route redistribution (default route), 409
RIP received/redistributed route filtering, 30
RIP route redistribution, 45
RIP routes, 31
RIPng received/redistributed route filtering, 382
RIPng route redistribution, 383, 392
refreshing
BGP route refresh enable, 269
removing
BGP private AS number from EBGP peer/peer group update (IPv4), 254
BGP private AS number from EBGP peer/peer group update (IPv6), 254
resetting
IPv4 BGP sessions, 299
IPv6 BGP sessions, 299
restrictions
RIP FRR configuration, 40, 388
RFC 1583 compatibility (OSPF), 90
RIB
BGP suboptimal route flush to RIB, 276
IP routing FIB route max lifetime, 4
IP routing RIB label max lifetime, 4
IP routing RIB route max lifetime, 4
IPv4 NSR configuration, 5
IPv6 NSR configuration, 5
additional routing metric configuration, 28
basic configuration, 26, 42
BFD configuration, 38
BFD configuration (bidirectional control detection), 40
BFD configuration (bidirectional detection/control packet mode), 58
BFD configuration (single-hop echo detection), 53
BFD configuration (single-hop echo detection/neighbor), 39
BFD configuration (single-hop echo detection/specific destination), 39, 56
configuration, 24, 25, 42
default route advertisement, 30
display, 41
ECMP route max number, 33
enable, 26
FRR BFD enable, 41
FRR configuration, 40, 61
FRR configuration restrictions, 40, 388
GR configuration, 37, 51
GR helper configuration, 37
GR restarter configuration, 37
host route reception disable, 30
interface additional metric configuration, 47
interface advertisement control, 27
interface reception control, 27
IPv6. See RIPng
maintain, 41
neighbor specification, 35
network management configuration, 36
network optimization, 32
network tuning, 32
nonstop routing (NSR) configuration, 52
nonstop routing (NSR) enable, 38
operation, 24
outgoing packet DSCP value, 37
packet max length, 37
packet send rate configuration, 36
poison reverse configuration, 33
poison reverse enable, 33
preference configuration, 31
protocols and standards, 25
received/redistributed route filtering, 30
RIPv1 message zero field check enable, 34
RIPv2 message authentication configuration, 34
RIPv2 route summarization configuration, 29
route control configuration, 28
route entries, 24
route redistribution, 45
route redistribution configuration, 31
routing loop prevention, 24
split horizon configuration, 33
split horizon enable, 33
summary route advertisement configuration, 48
timer configuration, 32
triggered update interval configuration, 35
update source IP address check, 34
version configuration, 27
versions, 25
basic configuration, 380, 389
configuration, 379, 380, 389
default route advertisement, 382
display, 389
ECMP route max, 385
FRR BFD enable, 388
FRR configuration, 387, 388, 397
GR configuration, 386, 394
maintain, 389
network optimization, 383
network tuning, 383
nonstop routing (NSR) configuration, 387, 395
packet, 379
packet send rate configuration, 385
packet zero field check, 384
poison reverse configuration, 384
preference configuration, 382
protocols and standards, 380
received/redistributed route filtering, 382
route control, 381
route entry, 379
route redistribution, 392
route redistribution configuration, 383
route summarization, 381
routing metric configuration, 381
split horizon configuration, 384
timer configuration, 383
triggered update send interval configuration, 386
RIPv1
message zero field check enable, 34
protocols and standards, 25
RIP basic configuration, 26
RIP configuration, 24, 25, 42
RIP versions, 25
version configuration, 27
RIPv2
automatic route summarization enable, 29
message authentication configuration, 34
protocols and standards, 25
RIP basic configuration, 26
RIP configuration, 24, 25, 42
RIP versions, 25
route summarization configuration, 29
summary route advertisement, 29
version configuration, 27
route
BGP default route advertisement (peer/peer group), 228
BGP IGP route redistribution, 223
BGP link state (LS) route reflection, 295
BGP MED route comparison (confederation peers), 247
BGP MED route comparison (diff ASs), 245
BGP MED route comparison (per-AS), 245
BGP optimal route advertisement, 227
BGP optimal route selection disable for labeled routes, 277
BGP ORIGINATOR_ID attribute ignore, 281
BGP route advertisement rules, 195
BGP route dampening, 238
BGP route distribution control, 224
BGP route distribution filtering policy, 231
BGP route filtering policy, 231
BGP route flapping logging, 286
BGP route generation, 221
BGP route preference, 241
BGP route reception control, 224
BGP route reception filtering policy, 235
BGP route recursion, 196
BGP route reflection, 280
BGP route reflector, 280
BGP route refresh, 269
BGP route selection, 195, 196
BGP route update delay, 237
BGP route update interval, 259
BGP route update save, 270
BGP route-refresh message, 191
BGP routes received (peer/peer group), 230
BGP suboptimal route flush to RIB, 276
IP routing FIB route max lifetime, 4
IP routing FIB table optimal routes, 1
IP routing inter-protocol FRR, 6
IP routing IPv4 RIB inter-protocol FRR, 6
IP routing IPv6 RIB inter-protocol FRR, 6
IP routing load sharing, 3
IP routing RIB label max lifetime, 4
IP routing RIB NSR, 5
IP routing RIB route max lifetime, 4
IP routing route backup, 3
IP routing route preference, 2
IP routing route recursion, 3
IP routing route redistribution, 3
IPv4 BGP route reflector configuration, 316
IPv4 BGP route summarization, 307
IPv4 BGP+IGP route redistribution, 304
IPv6 BGP route reflector configuration, 344
IPv6 default route configuration, 378
IPv6 IS-IS route control, 448
IPv6 IS-IS route convergence priority, 450
IPv6 static route BFD configuration, 368
IPv6 static route BFD control mode (direct next hop), 369
IPv6 static route BFD control mode (indirect next hop), 369
IPv6 static route BFD echo mode (single hop), 369
IPv6 static route configuration, 368
IPv6 static routing basic configuration (on switch), 370
IPv6 static routing BFD (direct next hop)(on switch), 372
IPv6 static routing BFD (indirect next hop)(on switch), 375
IPv6 static routing configuration, 368
IPv6 static routing configuration (on switch), 370
IS-IS default route advertisement, 145
IS-IS ECMP routes max, 144
IS-IS LSP-calculated route filtering, 146
IS-IS redistributed route filtering, 146
IS-IS route control, 142
IS-IS route filtering, 145
IS-IS route leaking, 146, 146
IS-IS route redistribution, 145, 173
IS-IS route summarization, 144
OSPF area configuration (NSSA), 113
OSPF area configuration (stub), 111
OSPF ECMP routes max, 81
OSPF host route advertisement, 83
OSPF preference, 81
OSPF received route filtering, 79
OSPF redistributed route default parameters, 83
OSPF redistributed route summarization (on ASBR), 79
OSPF route calculation, 68
OSPF route control, 78
OSPF route level priority, 68
OSPF route redistribution, 82
OSPF route redistribution configuration, 106
OSPF route summarization, 78
OSPF route summarization (on ABR), 78
OSPF route summarization configuration, 108
OSPF summary network discard route, 81
OSPFv3 ECMP route max, 408
OSPFv3 received route filtering, 407
OSPFv3 redistributed route tag, 410
OSPFv3 route control, 406
OSPFv3 route redistribution, 409, 432
OSPFv3 route redistribution (another routing protocol), 409
OSPFv3 route redistribution (default route), 409
OSPFv3 route summarization, 406, 435
OSPFv3 route summarization (on ASBR), 406
RIP default route advertisement, 30
RIP ECMP route max number, 33
RIP host route reception disable, 30
RIP poison reverse configuration, 33
RIP preference configuration, 31
RIP received/redistributed route filtering, 30
RIP route control configuration, 28
RIP route entries, 24
RIP route redistribution, 45
RIP route redistribution configuration, 31
RIP split horizon configuration, 33
RIP update source IP address check, 34
RIPng default route advertisement, 382
RIPng ECMP route max, 385
RIPng preference, 382
RIPng received/redistributed route filtering, 382
RIPng route control, 381
RIPng route entry, 379
RIPng route redistribution, 383, 392
RIPng route summarization, 381
RIPv1 message zero field check, 34
RIPv2 summary route advertisement, 29
routing policy filters, 476
static routing basic configuration, 14
static routing BFD configuration, 10
static routing BFD configuration (direct next hop), 15
static routing BFD configuration (indirect next hop), 18
static routing configuration, 9, 9, 14
static routing default route configuration, 23
static routing FRR configuration, 12, 20
router
BGP link state (LS) router ID, 296
BGP peer, 191
BGP speaker, 191
EBGP peer, 191
IBGP peer, 191
IS-IS interface P2P network type, 141
IS-IS IS+circuit level, 141
IS-IS Level-1 router, 135
IS-IS Level-1-2 router, 135
IS-IS Level-2 router, 135
IS-IS route leaking, 136
IS-IS routing method, 134
IS-IS system ID, 134
OSPF ABR type, 67
OSPF ASBR type, 67
OSPF backbone type, 67
OSPF internal type, 67
OSPF router LSA, 64
OSPF stub router, 87
OSPFv3 stub router, 414
routing
BGP load balancing, 265
IPv4 RIB NSR configuration, 5
IPv6 default route. See under IPv6 static routing
IPv6 IS-IS. See IPv6 IS-IS
IPv6 policy-based routing. See IPv6 PBR
IPv6 RIB NSR configuration, 5
IPv6 static routing. See IPv6 static routing
OSPFv3 route redistribution, 432
policy-based routing. Use PBR
tuning BGP network, 258
Routing Information Protocol. Use RIP
routing policy
display, 483
maintain, 483
rule
BGP route advertisement rules, 195
S
saving
BGP route update (IPv4), 270
BGP route update (IPv6), 270
security
BGP GTSM configuration, 267
IPv6 IS-IS prefix suppression, 452
IS-IS authentication (area), 158
IS-IS authentication (neighbor relationship), 158
IS-IS authentication (routing domain), 159
IS-IS network security enhancement, 158
OSPF authentication (area), 88
OSPF authentication (interface), 88
OSPF prefix priority, 93
OSPF prefix suppression, 92
OSPFv3 authentication, 416
OSPFv3 prefix suppression, 415
SEL
IS-IS N-SEL, 134
NET, 134
selecting
BGP load balancing through route selection, 196
BGP path selection, 239
BGP route, 195
BGP route selection, 196
IPv4 BGP path selection, 322
IPv4 multicast BGP configuration, 334
sending
IS-IS CSNP packet send interval, 148
IS-IS hello packet send interval, 147
IS-IS interface hello packet send, 149
IS-IS interface packet send/receive, 148
OSPF interface packet send/receive disable, 87
OSPFv3 interface packet send/receive disable, 412
RIPng packet send rate, 385
RIPng triggered update send interval, 386
session
BGP session establishment disable, 266
BGP session state change logging, 285
EBGP session establishment (multiple hop), 260
setting
BGP outgoing packet DSCP value, 276
BGP received route preferred value (IPv4), 239
BGP received route preferred value (IPv6), 239
IP routing FIB route max lifetime, 4
IP routing RIB label max lifetime, 4
IP routing RIB route max lifetime, 4
IPv4 BGP session reset, 299
IPv6 BGP session reset, 299
IPv6 IS-IS LSDB overload bit, 451
IPv6 PBR node match criteria, 469
IS-IS ATT bit Level-1 LSP, 153
IS-IS IS+circuit level, 141
IS-IS LSDB overload bit, 152
maximum OSPF packet length, 92
OSPF ECMP routes max, 81
OSPF exit overflow interval, 89
OSPF log count, 95
OSPF LSA arrival interval, 86
OSPF LSA generation interval, 86
OSPF LSA transmission delay, 85
OSPF LSDB external LSAs max, 89
OSPF LSU transmit rate, 91
OSPF packet DSCP value, 90
OSPF preference, 81
OSPF timer, 84
OSPFv3 ECMP route max, 408
OSPFv3 LSA generation interval, 411
OSPFv3 LSA transmission delay, 411
OSPFv3 SPF calculation interval, 411
OSPFv3 timer, 410
outgoing OSPF packet DSCP value, 89
outgoing RIP packet DSCP value, 37
PBR node match criteria, 360
RIP ECMP route max number, 33
RIP packet max length, 37
RIP preference, 31
RIP triggered update interval, 35
RIPng ECMP route max, 385
RIPng preference, 382
RIPng timer, 383
RIPng triggered update send interval, 386
SNMP
BGP SNMP notification enable, 285
OSPF network management, 91
SNP IS-IS PDU type, 138
soft reset
BGP manual configuration, 272
BGP soft reset, 268
SoO
BGP attribute configuration, 256
source
RIP source IP address check, 34
speaker
BGP, 191
specifying
BGP link state (LS) AS number, 296
BGP link state (LS) router ID, 296
BGP TCP connection source address, 220
BGP TCP connection source address (IPv4), 220
BGP TCP connection source address (IPv6), 220
IS-IS CSNP packet send interval, 148
IS-IS hello multiplier, 147
IS-IS hello packet send interval, 147
IS-IS LSP length, 150
IS-IS preference, 143
OSPF SPF calculation interval, 85
RIP neighbor, 35
SPF
IPv6 IS-IS calculation interval, 451
IS-IS calculation interval, 151
OSPF SPF calculation interval, 85
OSPFv3 SPF calculation interval, 411
split horizon, 33, 33
RIPng configuration, 384
state
BGP session state change logging, 285
static
IS-IS system ID > host name mapping, 154
routing. See static routing
basic configuration, 14
BFD configuration (direct next hop), 15
BFD configuration (indirect next hop), 18
configuration, 9, 14
default route configuration, 23
display, 13
FRR configuration, 20
IPv6. See IPv6 static routing
routing configuration, 9
static routing BFD bidirectional control mode (direct next hop), 10
static routing BFD bidirectional control mode (indirect next hop), 10
static routing BFD configuration, 10
static routing BFD echo mode (single-hop), 11
static routing FRR configuration, 12
stub
OSPF area configuration, 111
OSPF area configuration (stub), 74
OSPF stub area, 66
OSPF stub router, 87
OSPF totally stub area, 66
OSPFv3 area configuration, 423
OSPFv3 area configuration (stub), 403
OSPFv3 stub router, 414
suboptimal routes (BGP), 276
substituting
BGP AS number substitution, 252
summarizing
BGP route summarization, 224
IPv4 BGP route summarization, 307
IS-IS route summarization, 144
OSPF redistributed route summarization (on ASBR), 79
OSPF route summarization, 78
OSPF route summarization (on ABR), 78
OSPF route summarization configuration, 108
OSPF summary network discard route, 81
OSPFv3 route summarization, 435
OSPFv3 route summarization (on ABR), 406
OSPFv3 route summarization (on ASBR), 406
RIPng route summarization, 381
RIPv2 automatic route summarization enable, 29
RIPv2 route summarization configuration, 29
RIPv2 summary route advertisement, 29
suppressing
BGP 4-byte AS number suppression, 262
IPv6 IS-IS prefix suppression, 452
IS-IS prefix suppression, 155
OSPF prefix suppression, 92
OSPFv3 prefix suppression, 415
RIP suppress timer, 32
switch
OSPFv3 configuration, 423
system
IS-IS system ID, 134
IS-IS system ID > host name mapping, 154
T
table
BGP optimal route advertisement, 227
IP routing, 1
tag
IPv6 IS-IS interface tag value, 451
IS-IS interface tag value, 153
OSPFv3 redistributed route tag, 410
TCP
BGP configuration, 191, 203
BGP TCP connection source address, 220
IPv4 BGP basic configuration, 300
IPv4 BGP BFD configuration, 326
IPv4 BGP COMMUNITY configuration, 313
IPv4 BGP confederation, 318
IPv4 BGP configuration, 300
IPv4 BGP dynamic peer configuration, 337
IPv4 BGP FRR configuration, 330
IPv4 BGP GR configuration, 325
IPv4 BGP load balancing configuration configuration, 310
IPv4 BGP path selection, 322
IPv4 BGP route reflector configuration, 316
IPv4 BGP route summarization, 307
IPv4 BGP+IGP route redistribution, 304
IPv4 multicast BGP configuration, 334
IPv6 BGP basic configuration, 341
IPv6 BGP BFD configuration, 350
IPv6 BGP configuration, 341
IPv6 BGP FRR configuration, 353
IPv6 BGP route reflector configuration, 344
threshold
EBGP peer protection (level 2 threshold), 274
time
BGP holdtime, 258
timeout
RIP timeout timer, 32
timer
IS-IS LSP timer configuration, 149
OSPF dead packet, 84
OSPF hello packet, 84
OSPF LSA retransmission packet, 84
OSPF packet, 84
OSPF poll packet, 84
OSPFv3 timer, 410
RIP garbage-collect timer, 32
RIP suppress timer, 32
RIP timeout timer, 32
RIP update timer, 32
RIPng timer configuration, 383
TLV
IPv6 Interface Address, 447
IPv6 IS-IS basic configuration, 456
IPv6 IS-IS BFD configuration, 461
IPv6 IS-IS configuration, 447, 456
IPv6 Reachability, 447
topology
excluding interfaces in an OSPF area from the base topology, 83
IPv6 default route configuration, 378
IPv6 IS-IS ISPF, 452
IPv6 IS-IS MTR, 455
IPv6 static route configuration, 368
IPv6 static routing basic configuration (on switch), 370
IPv6 static routing BFD (direct next hop)(on switch), 372
IPv6 static routing BFD (indirect next hop)(on switch), 375
IPv6 static routing configuration, 368
IPv6 static routing configuration (on switch), 370
IS-IS ISPF, 155
Track
IPv6 PBR collaboration, 468
PBR collaboration, 359
static routing configuration, 9
transmitting
OSPFv3 LSU transmit rate, 414
trapping
BGP SNMP notification enable, 285
IS-IS network management, 156
OSPF network management, 91, 91
OSPFv3 network management, 413
triggered RIP (TRIP)
protocols and standards, 25
triggering
OSPF GR, 98
OSPFv3 GR, 418
RIP triggered update interval, 35
RIPng triggered update send interval, 386
troubleshooting
BGP, 357
BGP peer connection state, 357
OSPF configuration, 131
OSPF incorrect routing information, 132
OSPF no neighbor relationship established, 131
TTL
BGP GTSM configuration, 267
tuning
BGP network, 258
IPv6 IS-IS network, 450
IS-IS network, 147
OSPF network, 84
OSPFv3 network, 410
RIP networks, 32
RIPng network, 383
tunneling
BGP optimal route selection disable for labeled routes, 277
Type 1 external
OSPF route type, 68
Type 2 external
OSPF route type, 68
U
UDP
RIP configuration, 24, 25, 42
RIPng basic configuration, 380, 389
RIPng configuration, 379, 380, 389
RIPng GR configuration, 386
RIPng route redistribution, 392
unicast
BGP dynamic peer, 209
BGP dynamic peer configuration (IPv4 unicast address), 209
BGP dynamic peer configuration (IPv6 unicast address), 210
BGP FRR configuration (IPv4 unicast address), 289
BGP FRR configuration (IPv6 unicast address), 289
BGP peer, 207
EBGP peer group configuration (IPv4 unicast address), 213
EBGP peer group configuration (IPv6 unicast address), 213
IBGP peer group configuration (IPv4 unicast address), 211
IBGP peer group configuration (IPv6 unicast address), 211
IP routing configuration, 1
IP routing dynamic routing protocols, 2
IP routing extension attribute redistribution, 3
IP routing load sharing, 3
IP routing route backup, 3
IP routing route preference, 2
IP routing route recursion, 3
IP routing route redistribution, 3
OSPF network type, 69
updating
BGP MPLS local label update delay, 275
BGP route update delay, 237
BGP route update interval, 259
BGP route update save, 270
BGP update message, 191
RIP source IP address check, 34
RIP triggered update interval, 35
RIP update timer, 32
RIPng triggered update send interval, 386
V
value
BGP MED default value, 244
BGP outgoing packet DSCP value, 276
BGP received route preferred value, 239
IPv6 IS-IS interface tag value, 451
virtual
OSPF virtual link, 66, 75
OSPF virtual link configuration, 119
VPN
BGP multi-instance, 201
Z
zero field check
RIPng packet, 384
zero field check (RIPv1), 34